A Chemistry Question, Daily

Camphor and Rivanol (Ethacridine Lactate) - An interesting reaction

2011-11-27T14:21:00.000+02:00

Two days ago, while trying to clean a pimple with an antiseptic camphor solution, I accidentally used ethacridine lactate (Rivanol) instead. After realizing this, instead of first cleaning the rivanol stain and then applying the camphor, I directly cleaned it with camphor using a cotton pad. Suddenly a new white layer formed at the contact surface between the two layers of substance. The occurrence of a chemical reaction was obvious, and after repeating the experiment in lab conditions, I tried to understand the formation of this new product.

Camphor structure

Rivanol structure
As far as my chemistry knowledge could tell, camphor is a tricyclic ketone while ethacridine is a heterocyclic compound with two amino groups. Maybe, what happened was an amino-carbonyl condensation with the elimination of one molecule of water, I thought.

But then another question came to my mind. If so, which one of the two amino groups was the one responsible for the reaction? Which one would be more reactive? And last but not least, how would the nitrogen atom influence the occurence of the reaction?

What happened

Well, let's first consider all the possible occurring reactions. There are three main possibilities. One of them, the amino group on the eccentric ring would suffer an amino-carbonyl intermolecular condensation. The second scenario is the amino group on the heterocyclic ring undergoing the same process. Last but no least, the third possibility includes both groups reacting with camphor.

Scenario I

Scenario II

Scenario III

Obvious to me, was the fact that the heterocyclic group was more reactive than the eccentric one for two reasons. One of them is the fact that the inner ring is less aromathic than the outer ones, therefore more reactive.

The second reason involves the electronic effects applicable for the substance, more precisely the static inductive effects for the ethacridine lactate and the π electron displacements in the double bond of camphor.

Electronic effects in camphor

Firstly, we will take camphor. The massive hydrocarbon radical in C₈H₁₄C=O generates a rather strong -I (electron attracting effect) towards the Oxygen atom. This happens due to the fact that Oxygen is more electronegative than Carbon, having a tendency to attract electrons. Due to the same reason, the π bond of the double bond, composed of two electrons is attracted more towards oxygen. Therefore, oxygen develops a δ- partial charge, while carbon is doing the opposite, accumulating δ+.

Electronic effects in rivanol

While talking about rivanol, we must take two effects into consideration. One for the left outer ring, and one for the central ring. For the central ring, the positive charge of the Nitrogen atom attracts electrons greatly, therefore, a -I attracting inductive effect is felt by the heterocyclic ring. At the same time, the amino group charges with δ+ making it more electrophilic, thus more reactive.

On the other hand, the outer amino group undergoes the opposite process. The outer phenyl ring, has an aromathic nature, electrophilic by definition. In this case, a very small -I effect is affecting the -NH₂ group, thus accumulating a small δ- partial charge.

Out of the two possible reaction loci, after the previous analysis of the effects in both substances, we can easily draw the conclusion that the locus on the inner ring would be far more plausible for the reaction to occur there, than the other one. In other words, probably, all three reactions occur, but the most probable one would be the one in scenario I as shown below:

The real preponderant reaction

The New Compound

The new compund was a precipitate, initially yellow in appearance, but only due to ethacridin lactate coloration in the test tube.

Before and after the reaction

In fact, after subsequent washing of the precipitate, the yellow coloration faded away almost entirely, what remained being only a very pale yellowish tone of white.

The washed and dried precipitate

After washing and drying, I grounded the precipitate into a very fine powder. Looking under a microscope to the crystals of the compound I found out that they are long, thin and tend to stick together in the form of a stack.

The crystals of the compound viewed in blue light under an optic microscope

Another image of the crystals

In the end, I would like to add a few more images of the compound:

Strepsils - A FLurbiprofen pathway to synthesis

2011-05-25T16:42:00.001+03:00

Recently, I caught a cold which is why I took some pills (Strepsils) for sore throat. Curious by nature, I took a glimpse at the chemical composition of the medication. What I observed, was that the active compound in the pills was a substance called Flurbiprofen. Due to the phonetical resemblance to ibuprofen, a well known pain-killer, I made some research about its nature and its uses.

Not surprisingly, it resembles very much to (RS)-2-(4-(2-methylpropyl)phenyl)propanoic acid (more shorter ibuprofen). The difference lays in the substitution of the isoproyl radical with phenyl and the hydrogen atom in ortho with a fluoride atom.

Firstly, I thought of a method to synthethise the compound from phenyl lithium and fluorobenzene as main building blocks, both of which had to be produced from benzene.

Fluorobenzene

Fluorobenzene, was to be obtained by reducing the nitration product of benzene followed by diazotation. The diazonium salt was treated with tetrafluoroboric acid. To obtain the desired compound the reaction product was put to high temperatures.

Phenyl Lithium

The phenyl lithium, is more easily available. All is needed to do in order to produce it is to bromurate benzene in a FeBr₃ environment and after this to react the product with fresh lithium well kept under petrol before the reaction.

The main synthesis

The two building blocks must be first reacted in a moderate to highly acid environment. This way, biphenyl is produced. If directly available, all previous steps may not be taken into consideration, instead the usage of a more pure biphebyl reagent would be preferred.

The biphenyl will then undertake nitration in ortho. This way, when we alkylate with cloroacetic acid, the acetyl radical will be prone to go into the para position. The nitrate is then reduced with an iron and HCl mixture, next following a process similar to that in the innitial synthesis of fluorobenzene.

It is crucially important to reduce the nitro group after the alkylation due to the fact that in the opposite case, the acetyl radical would go into the ortho position yielding a totally different compound. Finally, flurbiprofen is obtained.

Generally, the sore throat medicines are made of an antiseptic and of an antiinflammatory drug. The antiseptic will reduce the microbian flora in the pharynx, while the antiinflammatory will reduce the prostaglandines and thromboxanes production, the root cause of the painful inflammation.

Despite being used for curing sore throat, its uses exceed this limited applicability. Due to the mechanism of action, flurbiprofene makes possible its use for treating the pain involved in different arthritis types of disease, a major relief for the great number of people suffering from a reumatical condition.

A Comparative Study of the Romanian Milk Brands

2011-05-15T20:39:00.000+03:00

About a month ago, I participated in a national chemistry contest, ChimeXpert for which I had to make a scientific poster based on my personal observations regarding a certain area of applied chemistry. As a consequence, I tried to find a subject close to my chemical study at school at that given moment, proteins, which is why I have chosen milk as a subject of study.

Purpose

The poster aimed to create an accurate comparative analysis of different Romanian milk brands' quality. The analysis was bound to answer to the need of information amongst the ordinary buyers. The analytical methods consisted in checking the compliance to quality standards of each dairy product selected.

Milk Facts

Milk is a complex liquid used as a food source by young mammals. Chemically speaking, the exact composition of milk varies from species to species, but it generally consists of water, fat, proteins and minerals.

Proteins

Cow milk contains numerous types of proteins (~3.4%), classically divided into two groups:

Globular Proteins: albumins, lyzozime, lactoferin, all playing vital roles in providing immunity for the newly born.
Heteroproteins - Caseins (proteins containing phosphorylated groups)
Caseins are proteins which are made of up to almost 200 amino-acid residues. H₂PO₃^- groups are attached to the serine residues, thus enhancing the reactivity of caseins towards calcium salts.

Caseins from milk come in many different sorts (α_S1 - casein, α_S2 - casein, k - casein, β - casein or λ - casein), all of which present coagulation properties at a pH = 4.6, except k - casein (due to a small number of phosphorylated serine residues in k - casein).

Fats

Raw milk has about 3.5% fats of which butyric acid is the most predominant fatty acid. It has been proved that butyric acid has anticarcinogenic properties, mechanism yet to be understood. Apart from butyric acid, milk also contains linoleic acids, octadecanoic acids and others as well.

Analytical Methods

For doing the study, I used six different brands: Milli, Zuzu, Rarăul, Covalact, Brenac and Tnuva. Two analytical methods have been used. The first one, is a quick but quite unaccurate method for analysing dairy products. It uses a device called LactoScan, based on the interpreting of ultrasonic resonance patterns of the milk being scanned.

Image: Lactoscan.com
The following charasteristics were measured: acidity, fat content, total dry substance (TDS), ash content (SOL), lactose content, proteic content, freezing point (crioscopic point) and density of the samples.

The coulours indicate the quality of the product:

bad, unsatisfactory, medium, satifactory, optimum

It can be easily noticed that the 6 brands generally comply to the ISO 22000 standard, except Brenac, which has a potential value of 17% added water (so as to reduce acidity of old milk), which is illegal. Moreover, almost all values for Brenac are out of standards.

The second approach to this analysis was the classical method. Through this method, I determined the pH and the acidity (in Torner degrees), the calcium content, and the eventual counterfeiting with NaHCO₃.

Acidity

Acid milk, generally old, is not proper for general consumption due to the excessive lactic acid formed by the Lactobacillus acidophilus in the milk.

CH₃CH(OH)COOH + NaOH → CH₃CH(OH)COO^-Na⁺ + H₂OTherefore the pH of the samples was tested (3 weeks before the expiry date). Normal milk pH is around 6.5. The six samples had a pH varying between 6.17 and 6.58, both values of which are within standards.

Counterfeiting

Generally, milk forgery is done in order to trick the acidity tests. Although illegal, the producers sometimes add NaHCO₃ or starch.

Testing for forgery with baking soda can be done by adding bromthymol blue. A normal milk would stay yellow-orange while a counterfeited one would turn green. All the samples have proven to be counterfeited with NaHCO_3.

When testing for starch, after boiling for two minutes and adding vinegar (to enhance coagulation) and iodine (starch detectiong purpose), the counterfeited tubes should have turned blue (as in the M tube used for demonstration purpose only), all the test-tubes turning out not to have been counterfeited with starch.

Calcium ions detection

Calcium is determined through a rather complex method. First, we have to reduce milk to ashes by heating in an oven at 600^oC for three hours.

The ashes are then incorporated into 50 ml solutions further brought to a pH af about 11.

Then EDTA (Ethylenediaminetetraacetic acid) is titrated into the milk ash solution in the presence of a few drops of murexide. The pink solution will turn purple.

The reaction involved in this mechanism is the following:

The calcium levels measured were at normal levels 800-1300 mg/L.

Conclusions

All the brands were more or less within standards, except Brenac, where severe disconcordances have been noticed. The best quality milk has turned out to be Covalact, respecting virtually all issues stipulated in standard with the exception of baking soda counterfeiting.

Outcome

At the contest, I have won the best poster award and a special award from the Romanian Inventors Forum.

Finally, you can find the poster here, in the version presented by me at the contest.

BizCamp 2010 - Day 1

2010-11-19T23:09:00.000+02:00

I am writing to share with you the experience I lived in the last two days, BizCamp 2010, a business camp for students. Here, through a series of workshops and sessions on the topics of success and how to achieve it, how to set goals, how to follow your dreams and many other personal development skills, I have met a whole bunch of extraordinary people and it was an incredible experience, really helpful for me.

Day 1

Day one was focused generally on the idea of reaching success. There were many speakers, each of them with a creative but very different style from the others. Among the ones who presented there was Alina Constantinescu, who talked about the importance of social media in gaining success and Mihail Musat who had some outstanding performances when being in front of the public.

She stated three principles that can lead to a success also determined by the personal network of relationships with the others. These principles are FIND OUT (be aware of the existing opportunities that surround you), CHECK OUT (show interest towards the others, create your network) and WORK OUT (get involved and be proactive).

Beside these steps, there were also some ideas that were outlined throughout the entire presentation:

Precaution can be dangerous when it doesn't make room for new opportunities.
When you start something new, begin with whatever you have and improve it later on in the process of building it.
The worst thing that may happen to you is not the lack of success, but the lack of anything happening to you.

Then, Mihail Musat, the founder of LumeBuna.ro tried to send us the message that success is a relative term. Therefore, my definition of success may be totally different from yours and so on. Interpreted in another way, even failure may be a means of succeeding due to the fact that we all should learn from our mistakes.

Through some simple examples and stories from his own experience, he succeeded (of course from my point of view due to the relativity of the term :D ) in getting across some simple but important ideas:

Never be impeded by your own thoughts. Never try finding reasons for a thing I want to do but for a particular reason it is "not recommended".
What will I choose? A potential failure or the lack of a potential success? (no pain, no gain)
It is much more important to know what I DO want than what I DON'T want.
Do things that you are passionate about.
"Experience is not what happens to a man but what a man does with what happens to him" (make proper use of your personal experience)

After that, there came a series of workshops that emphasized the importance of a mix between passion, work and creativity in your way to success, three elements that make a difference.

There were also some funny parts of the day, like when we were the first in our country to see the new Coca Cola cold season commercial :)

In the end it turned out to have fulfilled our expectations and it was definitelly a really nice thing to take part in.

Coming next - BizCamp 2010 Day 2 :D

Barbeque Chemistry

2010-11-08T23:57:00.000+02:00

Hello there! It's me again with a pretty unusual subject for this rather cold period of the year: barbeque chemistry. Why? Because it reminds us of the hot summer weekends when we attend outdoor barbeques and because I have read an interesting science paper regarding barbeque fuel tablets.

When we go out and make a camp fire we might use the traditional method of matches and wood or if we are more lazy, we could use those camp fire lighters such as liquid petrol or solid fuels for rapidly starting up a fire. Some are based on phosphorus while others rely on an organic compound, hexamethylentetramine, also called hexamine or urotropine and this is the compound I am going to talk in the next few lines.

Urotropine has a spatial structure, having the form of adamantane, the simplest diamondoid with the only difference that the four methine groups are replaced by nitrogen atoms. Therefore, the structure is the following.

Industrially it is synthesized from methane oxidized in air at 400 to 600 ^oC on nitrogen oxides so as to obtain formaldehyde. Four molecules of formaldehyde react afterward with six molecules of ammonia and urotropine is the result. The conditions under which the reaction occurs are temperatures high enough so as the formaldehyde and the ammonia to be in gaseous form.

The possible mechanism for this reaction might involve three steps. The first one would be an addition of NH3 to the formaldehyde. Therefore, NH2-CH2-OH is obtained. After this, the compound eliminates water and the aldimine CH2=NH is formed. Through trimerisation a cyclic compound is formed and further reacted with 3 molecules of formaldehyde and one molecule of NH3 will finally make urotropine.

The urotropine synthesized this way is the major product in the solid fuel tablets. They have the advantage of burning on any type of weather with a rather hot flame at about 760 ^oC. Moreover, these tables do not give off fumes due to the fact that the only gases released are CO2, N2 and vapors of water: (CH₂)₆N₄ + 9 O₂ → 6 CO₂ + 2 N₂ + 6 H₂O.

Image from: http://www.ebit.de/

It is important to mention that urotropine is used also to treat urinary infections due to its activation by the acids in urine but also as a precursor to many explosives such as HMTD, a compound suspected to have been used in the London underground terrorist attacks in 2005.

All in all, it's highly useful but it can turn out to lead to dangerous products so it is important to be used with care.

Colorant Synthesis

2010-11-04T22:11:00.000+02:00

Hello there once again! I have recently started a new chapter in my preparation for the Chemistry Olympiad, the azo compounds, very important for the production of azo colorants, mainly used as food colorants but also as dyes and other kinds of pigments. I was solving some synthesis problems until I got stuck at the synthesis of Naphtol Blue Black (structure shown below) from inorganic and organic substances with no more than two carbon atoms.

From the very beginning it was clear to me that I first had to make the naphthalene ring. Therefore I started from acetylene and made the necessary trimerisation in order to obtain benzene. Next, I used a Friedel- Crafts alkylation and obtained o-diethylbenzene, which through severe dehydrogenation at 400-600 ^oC yields naphthalene.

It is important now to arrive at the H-Acid structure, also called 1-Amino-8- Naphthol-3,6-Disulfonic Acid. In its synthesis it is vital to leave the formation of the amino group at the end so as not to be involved in any unwanted reaction made possible by the increased sensitivity of amines.

In its formation, firstly the naphthalene is nitrated and then trisulphonated. The third acid sulphite group in the α position is used for creating the -OH group through a process known as alkaline melting. The rest of the groups do not undergo this process because they are in less reactive β positions. Nevertheless, the other -SO3H groups suffer neutralization with NaOH and form ionic bonds between oxygen and sodium, thus replacing the hydrogen atom.

Finally the -NO2 group is reduced on iron and hydrochloric acid using 6 [H], produced by the following reactions:

Fe = Fe ³⁺ + 3 e^-

HCl = H⁺ + Cl^-
H⁺+ e^-= [H]

The H-acid is ready. Now comes the tricky part where I got stuck. You now have to do the coupling, but there is the problem of the lack of symmetry within the compound.

The preparing method for the diazonium salts to be used in the coupling reaction. Firstly a nitration followed by reduction on Fe/HCl and then diazotation with NaNO2 and HCl after the reaction:

Ar-NH2 + NaNO2 + 2HCl = Ar-N⁺≡N]Cl^- + NaCl + 2 H2O

If you couple in normal conditions a diazonium salt to our naphthalenic ring there will be two problems. First, it won't couple into the β position, α being definitely preferred by the reaction itself. Second, even if you succeed in coupling a diazonium salt into the β position, it will immediately occupy both β carbons.

But there is one thing that makes the H-Acid so suitable for this multiple coupling. On one of the rings in the naphtalenic cycle, we have phenolic -OH, while on the other we have an amino group -NH2. We can clearly see the difference, one is moderately alkaline while the other is acid.

This does matter because in the coupling we have to choose between acidic or alkaline environment. Therefore, the coupling near the alkaline -NH2 group will take place in acidic conditions whereas the coupling next to the phenolic -OH in an alkaline environment.

The first coupling in acidic conditions

The second coupling in NaOH environment and the final product

A sample of the colorant. Image from http://www.biomed.cas.cz/

Finally, the synthesis is done and we have our Naphtol Blue Black colorant. I considered this useful enough to be posted due to this special property of the H-Acid dictated by the presence of the two different groups that influence drastically the course of the reaction and because it is quite complex enough to bring in front an element of challenge. I'll also try to make it in the lab although I'm not sure I will succeed, being a quite difficult synthesis. See you next time!

Ask a Nobel Laureate and You Have a Good Chance to Receive an Answer

2010-10-03T21:45:00.004+03:00

Hello everybody! Last month I was surprised to see an email in my inbox from Rieko Kawabata, Programme Coordinator at Nobelprize.org inviting me to take part into the Ask a Nobel Laureate project, by asking a chemistry question to Professor Harry Kroto, Nobel laureate in 1996 for the discovery of fullerenes. From all the questions submitted a few were to be answered by Prof. Kroto himself. Therefore, I submitted two questions to Professor Kroto.
Two days ago, while searching for the answered questions, I found to my great surprise and happyness that both my questions have been answered, and I am transcripting his answers so as for you to have his answers also in text format. :)

Question 1

A: "Andrei Florea, two questions, question 12a:"
Q: "The mechanism for creating fullerenes is not yet fully understood. What would be the most likely explanation for that formation?"
A: "Well, it's pretty complicated, but it's quite clear that carbon is one of the fastest nucleating compounds, atoms or elements that we have and it zipps up to thousands very quickly from hot plasma and carbon molecules and graphites, these are down to actually melt, in fact no one seen liquid graphite to my knowledge, or liquid diamond... but I think what happens is from carbon atom plasma that we produce with a laser and we vaporize graphite, carbon chains first form, I think, liniar carbon, liniarish carbon C1, C2, C3, C4, C5, C6, so on; and my colleague David Walton really had a briliant way of making carbon chain molecules with just things on the end, so it was quite clear that you can make carbon chains of 30 or more carbon atoms. My guess is, what is happening in the range when they get to a 18, 19, 20, other things are forming and we think that there are also monocyclic rings forming in which the chain turns into a bead chain, you know... a ring carbon atoms in a monocyclic ring. I think that's now been proven by some really neat science by John Meyers Group in Basel and it was conjectured many years ago by theoreticians; then at around 20 to 30 to 40 to 50, I think these coalesce into cages and these cages may and we're pretty sure, we've got some results here a student pulled on working with myself and we showed that there are definitely spiecies with 28 carbon atoms which are cages, these circumstantial but nevertheless pretty definite cage structure. So at that point you've got your little baloons, if you wish. I think what happens then is carbon atoms and carbon molecules coalesce into this... ingested into this network of C40, C50 and so on and when they hit C60, they hit the first stable structure. C60 is the first stable fullerene. So a lot get locked into that, some get shooting on to C70 and others to higher ones. As you get these and you extract them, 10% of the soot, which are large particles, are in the form of fullerenes, sort of like, 80% to 90% C60, about 10% C70 and a few percent all the others with more and more carbon atoms and of course nanotubes and many other things. So, basically, I think that you have this cage forming at small levels and all others are being ingested into this structure and they stop when they get to C60 and that's why C60 is strong. And I think that's about as far as I'm prepared to go; it's just very, very complicated. Now people have been looking at the combustion process for 50 years, theorising and doing experiments. And they missed C60, so not sure they got it right, I don't know... it's very complicated and I think the best theory is my... theory; it all comes together. Best I can do."

Question 2

Q: "It has been proven that when chloroform is added to fullerenes, their structure changes from a cubic network of buckyballs to a hexagonal one, a process with impact on superconductivity. Why does this structural change occur?"
A: "Well, I don't know... I think the difference between hexagonal and cubic packing is a very, very low energy barrier, or a very small difference in barrier, so the impact of an intercalated molecule will be quite strong and the intermolecular forces will favour in the case of the chloroform structure, the hexagonal one."

In the end, I would like to thank Professor Harry Kroto and the nobelprize.org team for this incredible opportunity that I've been given and to invite you all to Ask a Nobel Laureate. :D

Surgery through the eyes of a teenager - Day 6

2010-08-31T22:36:00.000+03:00

Day six, simply awesome! We spent all day in the intervention I was telling you about in the last post, with Dr. Halpern and three colleagues of him trying to fix the aortic aneurysm rupture in the patient. In the evening we were exhausted from staying on two feet for about eleven hours, but we were all happy that the intervention seemed to be a success.

When we got into the operation room, the patient was already laying on the table, prepared for the anesthesia. He received both spinal block and general anesthesia, the general one being for not feeling anything during the intervention and the spinal one for relieving the possible postoperative pains. The patient was quite cooperative and the anesthetist put him to sleep in almost no time, thus allowing Dr. Halpern to place the patient in a comfortable position for the surgeons to operate properly.

After having this done, Dr. Halpern, assisted by another colleague, started performing the whole procedure. Firstly, an incision would be done somewhere near the patient's shoulder so as to expose the axillary artery.

He had to cut through a superficial layer of subcutaneous fat and after that, through the proximal end of the pectoralis minor muscle so as to reach the artery. Once the artery reached, the team anastomosed (attached) a polytetrafluoroethylene (PTFE) prosthetic graft to the artery. This was done with the use of a very thin thread of polypropylene wire, similar to the one we had used for performing the fistula intervention in the first day.

The surgeons consequently attached to the graft a device called visceral perfusion system (octopus), basically a device which split the blood supply into four, one for each of the four major abdominal arteries that would have been left short of blood supply when they clamped the aorta so as to remove the aneurysm. The device was composed of different cannulae, all plugged one to another in a tree-like configuration.

Here was the first cannula inserted into the PTFE graft

Then, the surgeons opened the patient's thorax between two ribs, by cutting through intercostal muscles. Using a special device, they enlarged the space between the ribs. At that stage we could clearly see the lungs with some pretty black odd spots covering them (maybe due to smoking?). We could even make out the heart beating at pretty high rates and the anesthetist could even read on the ECG scan some abnormal extrasystoles when touching the heart with the hands or with surgical instruments.

You can clearly see the left lung of our patient in this picture

In this 5 seconds video that I've made, you can distinguish the beating heart in the open thorax of the patient

After this, Dr. Halpern cut the patient's abdomen and one rib into half so that he could have easier acces to the aorta, introduced the octopus into its place in the four major arteries, one branch of the device per artery and finally clamped the aorta at the thorax level. Thus, the blood could pass from the heart to the viscera through this external "piping system" and not suffer from no blood supply while the aorta was clamped.

Here, the four plastic tubes are the branches of the visceral perfusion

Consequently, the team put another synthetic tube so as to replace the aorta, united the celiac artery, and the renal arteries were anastomosed together at the distal end of the prosthetic graft, while the superior mesenteric artery was attached to a smaller graft anastomosed at its turn, right into the middle of the prosthesis, used to replace the piece of aorta suffering from aneurysm.

Immediately after that, the surgeons started putting back in place the lungs, sewing back the ribs and suturing the wounds.

You can see the rib and the doctors' hands sewing it together

Finally, blood draining tubes were inserted into the patient's leg so as to collect any possible blood from postoperative hemorrhages. The axillary prosthesis was removed and the artery closed, in this way finishing the operation.

Nevertheless, the most amazing thing I noticed, what not on the 6th day I'm talking about in this post, but this morning (the 7th day), when Dr. Halpern came in and told me that last night he had an emergency, and had to operate from midnight until 7 AM another aneurysm, infrarenal this time, which is an operation as big as the one described here. So more than 20 hours of almost continuous work requires a lot of resilience from the surgeon and an ability to focus day and night without break.

This was the last day of "Surgery through the eyes of a teenager" series and I hope you enjoyed this fantastic opportunity of peeking through into the surgical world.

To sum up, it was an incredible experience and I believe it strengthened my resolve to follow the path of medicine. I would also like to thank Dr. Halpern once again for taking the responsibility of my being there and I also invite you to say your opinion regarding this 6 days experience of mine. See you soon!

Surgery through the eyes of a teenager - Day 5

2010-08-29T20:22:00.000+03:00

Day five was expected to be a very busy one due to a major intervention that Dr. Halpern was supposed to perform, accompanied by two or three other colleagues.

In short, the patient had an aortic aneurysm (an abnormal blood-filled dilation caused by the weakening of the blood vessel's wall) and due to the friction between the aorta and the spinal cord, both of them had to suffer: the spinal cord being eroded and the aneurysm being partially ruptured, all that kept it from hemorrhaging being the pressure of the viscera that were surrounding it. Therefore, the risks of an internal bleeding have risen with every moment passing by.

Image from: Reed Group

Taking into consideration the facts mentioned above, Dr. Halpern considered the operation imperative to be made on Friday, 27th of August, the day I'm talking about in this post. Even so, at about 10 AM, the anesthetist came into Dr. Halpern's office and informed him that for the operation to be made, there was a necessity of minimum ten 500 ml containers of red cells, plasma and platelets. Unfortunately, the hospital had at its disposal only four containers of red cells and the transfusion center could only have sent another three bags of erythrocytes and two of platelets, anyway, far from enough for the intervention to be considered sufficiently safe to make. This is why we have to wait until Monday (tomorrow) for the operation to be done.

Of course, there are many risks for the patient to wait for a blood supply, mainly due to life threatening bleedings, but the options have been carefully balanced and this seems to be the least harmful decision.

To sum up, this experience has shown me how important is synchronizing in every detail of an intervention within all members of the team, even from different departments and also how dramatic can the absence of some materials essential for keeping the patients alive be.

In other words, tomorrow (day 6), I will take part at this terribly difficult intervention and of course I'll bring you details about it in the next post.

Surgery through the eyes of a teenager - Day 4

2010-08-29T18:16:00.000+03:00

Day four started in a normal way, at the morning shift report everything seeming to be fine, there being no emergencies for the day, except some planned beforehand interventions such as getting rid of varices, draining a phlegmon, etc. Dr. Halpern was assigned to drain the phlegmon, a nasty infection that was situated on the patient's foot.

Just after entering into the operating room, it was clear for me judging by the fetid smell that, because of the nearby phlegmon, one of the toes had suffered necrosis. Dr. Halpern's decision of amputating this toe had been taken incredibly fast and I was taken aback by the speed of the action: the surgical pliers cut the toe within a blink of an eye and I can still recount the crunching sound of the bones. Then, he cut the phlegmon open and brought out the infection source before starting to cut other necrotised tissues. Unfortunately, the metatarsus of the forth and fifth toes were also infected, so he had to cut both the fifth toe and the metatarsals of the fourth and fifth toes too. Due to the removal of the fourth and fifth metatarsals, the amputation was called a fourth and fifth ray amputation.

After making sure there is no visible sign of infected tissue left in the wound, Dr. Halpern poured betadine (Povidone-iodine), a iodine based polymer disinfectant widely used in surgery. Consequently, he dressed the wound, although without doing any suturing. For the next few weeks, the nurses will have to take care to dress it daily, by cleaning the wound, removing any blood or possibly reinfected tissue with a surgical aspirator (a very painful procedure done without the use of any anaesthetics) and redressing it again.

Nevertheless, there is also a good part in the fact that the operation only removed two toes. What I am trying to say, is that an infection of these proportions could have done much worse damage to the leg. Moreover, the last two toes are important but not essential for walking, as Medical Disability Guidelines mention on their site ("Amputation of the third, fourth, or fifth toes usually results in little disability").

Although it was quite a nasty operation, I consider that it is important for me to know that there are also less pleasant interventions too, because they do represent a part of the hospital life as surgeons know it.

Surgery through the eyes of a teenager - Day 3

2010-08-26T23:41:00.001+03:00

Today, as I entered the hospital's building, still thinking about the operation a day before, I joined the morning visit and then the shift report. Here was raised the problem whether the hybrid intervention performed in the previous day had been indeed more convenient than a series of smaller operations or not. The debate lasted for about ten minutes and the final answer was positive due to the fact that those structures that were affected by blood vessel narrowings were very close one to another, thus making more sense to operate them all together.

After the shift report meeting, Dr. Halpern was supposed to have an aortofemoral bypass intervention for an old lady with an occlusion in both the common and external iliac artery. In this case, he would have had to bypass the right external iliac artery and the upper part of the femoral artery with an artificial graft.

Image from: Healthwise Inc.
Nevertheless, the operation turned out to be inappropriate to perform at that time, due to several reasons. The main reason was that of an endocrinological problem of the patient. To be more precise, the thyroid gland was oversecreting hormones that made the patient to have a heart rate of about 130 beats/min, a very big heart rate at her age. If she were to be operated, the anaesthetic could have accelerated her heart rate even more, which could have lead to myocardial infarction, an almost sure death on the operating table. Therefore, the patient went for an endocrinological consult and consequently, she has been prescribed medication and the intervention has also been delayed. The bad part is the fact that at any time blood can totally stop running through the vessels in her leg. In this way the oxygen supply is cut off, so the muscle in her leg can do nothing more but resist a few hours before dying. This would surely lead to necrosis of the tissue, the only surgical treatment left in that case being amputation.

So, Dr. Halpern made the discharge papers telling her to come back two weeks from now on, when her heart rate will have ceased to beat at such high speeds. Of course, there is always the risk of having to undergo an amputation intervention (proportional with the amount of time elapsed from the discovery of the ischemia), but this may have to be done in order to keep the patient alive.

Although there was no thing such as an intervention in the third day, I realize I had the opportunity to peek through the relation between medical staff and patients, the means and methods of telling both good and bad news to the patient, which is definitely one important thing in what truly means hospital life. See you tomorrow!

Surgery through the eyes of a teenager - Day 2

2010-08-25T22:23:00.001+03:00

The first day in the operating room may have been very interesting but the second day was a truly amazing experience for everybody, I believe. At 8 AM sharp, the entire medical staff gathered for the daily visit paid to all the patients. Here they analyzed the progress each of the patients made, which of them should undergo an operation and which of them should be discharged. After that, I attended the shift report, where the day's schedule was settled as well. I found out that Dr. Halpern was supposed to do a hybrid surgical intervention, combining a femoral artery bypass downwards, from the upper part of the thigh towards the upper quarter of the leg, with two stent insertions into the same artery but upwards. Dr. Halpern was responsible together with another colleague surgeon, for performing the bypass manoeuvre. After that, two other surgeons using the help of the two, would insert the two stents under live X-ray scanning on the patient, so that the surgeons would not be blindfolded when introducing the stents.

The patient's femoral artery, common iliac artery and also external iliac artery, had several atherosclerotic narrowings. Therefore, because of their position on basically the same long blood vessel, a radical decision was taken. Instead of undergoing multiple operations, all the problems were solved in only one big intervention. It basically implied the harvesting of the great saphenous vein and attaching it to the femoral artery by anastomosis (suturing in place) with the reversed portion of the saphenous vein previously harvested. Here, the surgeons realized that the saphenous vein that they had already connected, was too long. Therefore, they had to cut it into half and then remove another extra 2 cm, followed by sewing the two pieces together. This wasn't a major complication, but it cost the whole crew a precious quarter of an hour.

Then, under live X-ray scanning, the two 8 cm stents were introduced: first came the one that should have fit into the common iliac artery and only after that, the one for the external iliac artery. This went exactly as planned. The live X-ray scanning was the only moment that I couldn't attend due to the fact that the stock of lead coat aprons had been exhausted and obviously I could not take the risk of exposing myself to X-rays.

The final step was suturing the whole length and depth of the wound back into place. This was again done with some difficulties in the end because a 5 cm portion of the 50 cm long and 15 cm deep wound started bleeding from inside out, and all the suturing in the area had to be undone in order to stop the bleeding. In the end it turned out to be a complete success.

Although painfully tired, with a backache and a neck pain from sitting upright close to the surgeons, I felt extraordinarily, due to what I saw in those more than 8 hours of intense surgical intervention, an intervention done only once before that in Bucharest, also by Dr. Halpern.

If fascinated as I was when seeing the whole thing taking place in front of my eyes, then catch up with tomorrow's post! :-)

Surgery through the eyes of a teenager - Dr. Rafael Halpern

2010-08-25T00:37:00.000+03:00

A few days ago, my father had a pretty nasty boil. Therefore he decided to go and operate it at one of his dearest childhood friends, Dr. Rafael Halpern, who is a vascular surgeon at the "Prof. Dr. C.C. Iliescu" Institute of Emergency for Cardiovascular Diseases in Bucharest, one of the most prestigious hospitals in Romania.

My father told him about me and my ambition to follow medicine at one of the top European universities. As a very kind person he is, Dr. Halpern offered to take me daily, all day long, to see how hospital life really is with its ups and downs, from the beauty of some spectacular interventions to the routine of paperwork, all blended together in what we call today vascular surgery.

Very excited, I took up his wonderful offer, and until now I do not regret a single moment. These two days that I spent there have shown me how equally interesting and overwhelming with responsibility this job may be, but also that you ought to have nerves of steel, qualities reunited in Dr. Halpern, who turned out to be really dedicated to his work. To sum up, he is a very balanced person that I would like to thank for his volunteering spirit shown in helping me with professional orientation!

Surgery through the eyes of a teenager - Day 1

2010-08-24T23:36:00.000+03:00

This week I am in Bucharest and I have the incredible opportunity to sit next to a vascular surgeon at the Institute of Emergency for Cardiovascular Diseases "Prof Dr C.C. Iliescu" and to watch closely all his activity. I am going to go from the shift reports to the visits paid to the patients, to individual consultations and even surgical interventions, all that for which purpose? Well, I really take into consideration following medicine in university and this experience would eventually show me if I am suited for this kind of job or not.

Day 1: A brachiobasilic fistula

First thing in the morning, we went to the medical shift report. The point of the meeting was exchanging essential patient care information with other medical and nursing staff, including eventual complications and surgical procedures applied on different patients.

After the report was over, we went into a cabinet in order to consult two cases, one of which would have been operated by the surgeon that I follow. The whole point of the operation was to create a way the man could undertake dialysis treatment. The intervention was supposed to bring together the brachial artery and the basilic vein, in a process called brachiobasilic anastomosis, thus creating what is known as a fistula, an unnatural bond between an artery and a vein, usually present as a hereditary malformation, but here representing the result of the whole surgical procedure.

The reason why the artery and the vein are bonded together is quite simple. Veins are superficial blood vessels, while arteries are more profound. Unfortunately, by their nature, veins transport the blood slowly, whereas the same blood flows much faster in arteries. But for a dialysis machine to work, it must be connected to a superficial blood vessel with a significant flow speed of the blood. A vein is good because it is superficial, but it must be attached to an artery due to the high blood speed necessity.

The connection was made between the basilic vein (marked on the image) and the red artery crossing nearby.

The operation could have been made even between the brachial artery and the cephalic vein, which is generally accepted as a better solution, but not in this case due to an edema that was present on the man's arm.

The operation itself consisted in three major parts: finding the vessels, bonding them and suturing the wound. When trying to find the two vessels through the layers of conjunctive tissue, we also ran across the medial nerve, an essential structure that we were ought to leave intact. When found, both the basilic and brachial artery were pinched with so called bulldog clamps, metal devices that did not let to pass the blood when applied onto the blood vessels. The bonding was realized with a hair thin thread of polypropylene. The secret of connecting the two vessels together consisted in knowing how to sew them so as not to let blood pass through. When the linking of the two was realized, the blood circulation was reopened, and the flesh sutured back into place. All in all it took approximately two hours, and it went very well, with no complications.

For me, it was an extremely interesting first operation ever to assist and also a very interesting day. See you tomorrow with another surgical story!

Alpha Leadership Bootcamp 2

2010-08-19T16:18:00.000+03:00

After the outdoor adventure day, we were all pretty exhausted so not many of us joined the meditation in the evening.

Day 5: Photoreading

In day 5, the things didn't turn as expected. Due to the fact that in the previous days we covered anticipation and alignment, in day 5 we thought we would discuss about action. What we did, was photoreading, similar to speed reading.David, the trainer told us about different techniques so as to photoread properly, all of them mentioned in the book Photoreading, 3rd Edition. Some of these techniques were skimming the book with no purpuse at first, then just looking at the pages with defocused vision so that the subconscious mind would perceive part of the information although we did not realise, and in the end just picturing the book line by line, whilst not hearing what we read inside our heads.

Day 6: Action

Finally, the last chapter, ACTION. After the regular morning exercise, we entered the training room and the trainer, Cristian, started a very nice talk about how each of the four types of intelligence (IQ - Mental Intelligence, EQ - Emotional Intelligence, FQ - Physical Intelligence, SQ - Spiritual Intelligence) match the neurological levels.

Cristi and me

After the break, we discussed the importance of mindmapping, due to the fact that it helps a lot to categorize different actions to be done in a precise way, thus simplifying thing a lot. Everynody knows that we can find something easier in a logically structured place than in a total mess up. That also applies to the human mind.

In the end we covered time management, because it represents a problem for many of us.

When the night finally had fallen, we went outside and enjoyed the camp fire. We also learned how to breathe fire. It helped, because it is useful to overcome fears. At the end we revealed our secret frientd's identity (the secret friend was a person that we had to secretly take care of during the entire period we stayed there).

Breathing fire

Here we were searching for constelations

Because we were accompanied by a romanian pop singer, from aband called Hi-Q, I had the inspiration to make him a surprise by asking the DJ to put some of his music. We all enjoyed it and Mihai's presence.

Day 7: Departure

Well, before leaving, we had a last training session so as to integrate all concepts learned into one. Andy, the trainer, also gave us some usefull pieces of advice to follow when we would have gotten back into "the real world". Now we are meeting weekly in Bucharest, but unfortunatelly I couldn't atend any of the meetings until now. Hope I would be able next week :D

If you want to join us next year, you are welcome and you can find further information on http://alphaleaders.ro/. These were the last 3 days at the bootcamp. For the first four of them go here.

See you soon :D

Alpha Leadership Bootcamp

2010-08-18T18:55:00.000+03:00

Hi there again! During my absence I have been to a bootcamp called Alpha Leadership, an experience that I consider worth shharing with you. It lasted seven days and it concerned leadership inside our inner selves. We had ten trainers (3 of them were british) with whom we did both intensive training and individual coaching sessions, but also outdoor activities as you should see further on.

Day 1 - The arrival

After spending some four hours on a bus trip from Bucharest to Sibiu through some beautiful places such as the Olt Defile we finally reached Sibiu, from where one of the trainers took us to the place where the bootcamp was going to take place, the Sibiel Guesthouse, a really nice place up in the mountains near the village of Sibiel.

In the same evening, the first training started at about 7:30 PM. We met the trainers and the organizers, Andy Szekely and Dan Luca, two very inspiring persons who made a concice but impressive presentation of the whole Alpha Leadership Bootcamp concept, how was it born, its mission and of course some details about what was going to happen in the next seven days. Moreover they talked about the "instruments" that we would use in the next few days and what effect each and every one of them might mave.

Day 2 & 3 - Training: Anticipation & Alignment

We got up at 6:30 and went to the morning streching. There we were taught both exercises for our body, but also for the mind to get focused. We were advised to set an intention for that day and in the evening to see if it came true or not.

Before the training could start, the trainers told us about alpha leadership. The term was coined with reference to the alpha pair that lead a pack of wolves. It implies having a well balanced inner self so that, when facing a decision to be made, the decision can be objective and calmly taken. Andy, the trainer of day 2, in order to illustrate the whole concept, quoted Mark Twain: "Before negotiating with others, finish negotiating with yourself"

The training was about the cycle that every α leader would pass through when dealing with a situation, and these are Anticipation, Alignment and Action (the 3A's). This means that when dealing with a difficult situation, we do not have to be taken aback by its effects, in contrary, we have to anticipate potential problems. Consequently, we have to align with the cause and with ourselves, by accepting the problem, by finding inner values that will help deal with the situation and by finding a solution that would involve minimum effort but maximum results. Only after that, the third step, the action itself.

Some of us in the middle of the training session

I particularly liked one of Andy's examples reffering to the 3 A's. He mentioned a martial artist. He anticipates the opponent's strike, he grabs the rivals fist just before hitting, and after that continues the movement of the opponent's arm into his own advantage. The action represents just the final part, that of the knock out. I liked this example, because the 3A's implied here do not refer to leadership upon other, but to leadership within ourselves.

We also had what was called a FLEX time (flexible time, free time) in which many of us using the help of a specialist in osteopathy enjoyed literally bone cracking sessions. It was great because it straightened up the body and it renewed the energetic level of the whole organism.

Enjoyable, ha? :))

In the evening we meditated in order to relax our bodies, but also to maintain our focus.

At 12:00 PM, after 18 hours of intense trainings we finally went to bed. And this happened daily.

We also learned some NLP techniques of getting rid of bad habbits, photoreading & speed reading techniques, we learned how to set values, and we were tought about the neurological levels of human mind, and how a shift in one of them could affect the others.

Day 4 : Outdoor

In this day, we got outside, gathered into teams and started doing activities, variating from building a village to carrying logs on your back while crossing a river on a rope. All in all we had lots of fun, but besides, we have learnt how important teamwork is, because all tasks were impossible to do without the involvement of the whole team. Here, pictures tell you more than the words :)

Just playing a game

Crossing the river

Jumping over a rope

Through the net

To Be Continued

Does anybody know?

2010-03-29T19:08:00.000+03:00

Hello there again. I have an interesting chemical experience to share with you. Yesterday, I had some fountain-pen ink on my fingers. As I was using sodium hydroxide to ease the flow at the used water drain, I accidentally spilled some onto my hands, over the blue ink. Almost instantaneously, it turned crimson red.

I tried to find out what the ink was made of, in order to determine the reaction that occurs, but I didn't find anything on the Internet.

Anyway, I know some details about both the ink and the reaction, and I have some photos taken afterwards when doing the experiment properly. The ink was Schneider (just in case any of you knows the composition :D ). The pH (measured by me with litmus paper) of the ink was around 6.5 and that of the final product was about 13. The sodium hydroxide was 50% in the solution. It also contained NaClO. Here I have some photos during the experiment.

In conclusion, if any of you happens to know what is going on over there, please leave a comment with your opinion.

The Schneider ink

The NaOH / NaClO solution

The upper ring is the final product after pouring in the ink

Liquid Calcium Hoax

2010-01-24T21:11:00.007+02:00

Hello guys! I bring good news to you. I am qualified for the National Level of the Romanian Chemistry Olympiad 2010, which will take place this year at Pitești, a nice city, where I've lived for almost half a year in 2004. I am quite happy about my results at the county phase, but I would like to believe this year will show up to be more rewarding than the previous one :D Unfortunately this year the Olympiad has no website, which is pretty annoying because we can't get any kind of updates about it. Although there is no way of directly receiving information about the Olympiad, my teacher has sent me the syllabus, which includes hydrocarbons (alkanes, alkenes, alkynes, polyenes and aromatic hydrocarbons), alcohols and just might include phenols, but that's not for sure.

And now, a little thing I've noticed on a Colgate® toothpaste tube:

On the back of the tube, it said: "contains liquid calcium". Well, chemically speaking, liquid calcium is obtained when you heat it to 842 °C in an environment lacking oxygen, because if oxygen would present self ignition of calcium would happen. So, clearly, this can't be the case admitting the last time I checked, I wasn't brushing my teeth with a molten hot red paste :))

Maybe they wanted to say "a liquid solution of CaF₂", but again it has to be a very, very diluted one, judging that the solubility in water 20 °C is roughly 0.0016 g/100 mL. Therefore, even this more scientific formulation is quite improper, though this might not be just a minor mistake, but more like an eye catchy description for customers to buy it. Nevertheless, everything should have a scientific basis, which in this case lacks somehow. Hope I wasn't too harsh :D

Image from www.bigoo.ws

Fluorescein, a Pathway to Synthesis

2009-12-03T19:37:00.013+02:00

Today, during a chemistry lab that I take at the local University (unfortunately lab sessions lack in our high school so I have to do and mend somehow), we were expected to synthesize the fluorescein. So, with excitement, we started to work. For the synthesis to take place, I used phtalic acid and resorcinol (or 1,3-benzenediol). As a catalyst it is recommended to use ZnCl₂, but I used concentrate sulphuric acid (purity >99%) instead.

Substances needed: resorcinol, phtalic anhydride (or phtalic acid), zinc chloride, sodium hydroxide, water

Glassware needed: a crucible, a bunsen burner, 2 berzelius flasks, one pipette

Working technique

In a small crucible, a few grams of solid phtalic acid and an equal amount of resorcinol are added. Followingly, the crucible is put on the sand bath at around 200^o. After the mixture melts, it is left boiling for about 40 minutes.
The molten mixture is cooled for five to ten minutes and then moved to a berzelius flask. Now NaOH 10-20% is added. As a result fluorescein will be generated and the mixture will turn from dark brown to light green.
Using a pipette, take five millilitres of the green dye and dillute it to about 10%. A light green fluorescence phenomenon will be observed in dim light, or in UV light. And here is the result :D (image taken by myself)

Tips

Although this is the first time I synthesized this compound, from the experience of others, I can draw a few conclusions from this experiment:

You can use, not only ZnCl₂, but also CaCl₂ as a catalyst.
If you choose to work with highly pure sulphuric acid as a catalyst, as I did, be extremely cautious of the way you are handling the acid, because is highly corrosive, especially in these concentrations (98-99%)
Instead of phtalic acid, phtalic anhydride works as well. The reason for this, is that at these temperatures (~200^oC) the acid is obliged to eliminate water, so anhydride is formed, that further reacts with resorcinol.
And the most important, have fun :p

Applications

"Fluorescein sodium is used extensively as a diagnostic tool in the field of ophthalmology and optometry, where topical fluorescein is used in the diagnosis of corneal abrasions, corneal ulcers and herpetic corneal infections. It is also used in rigid gas permeable contact lens fitting to evaluate the tear layer under the lens." - excerpt from Wikipedia One of its less common uses is the annual festival of St. Patrick's Day, when the Chicago River's waters are dyed green. Image from Wikipedia And now, as an ending, a couple of other images concerning the experiment today:

ChimeXpert International Competition Begins Today

2009-11-16T19:54:00.004+02:00

The first phase of ChimeXpert International Chemistry Competiton has started today. This phase consists in a set of three tests on the internet, for those of you who have already registered and paid the registration fee of 40 RON (12 euro). All three tests are multiple choice type, with 40 questions. The solution for the first test can be submitted on their site until the 28^th of this month (November).

All competitors who fill in all three tests will go to the regional phase where the real selection will take place. The marks at these three tests are used for selecting the contestants that will go further to the International phase in case of equality between the first scores at the regional phase.

Good Luck!

The mistery of the water droplet

2009-11-11T20:31:00.004+02:00

Yesterday, as I was in the chemistry lab, working at an addition reaction to an alkene, I needed to use a bunsen burner, for the preparation of the proper alkene. As one of the rubber tubes was leaking, I took a roll of aluminium foil in order to wrap some around the portion of the tube with the little hole in it. Accidentaly, I dropped the foil directly above the flame. It immediately turned red hot. And because I had my hands wet, a droplet of water fell on the aluminium foil. Then, a very strange thing happened. Instead of vapourising instantaneously, the droplet persisted on the foil for about 15 seconds. Judging that the aluminium foil turns red at temperatures clearly higher than 100^o C, the water drop was expected to vapourize in a far smaller period of time. Moreover, the water drop became rather spherical, as it seemed to have fallen on a hydrophobic surface. At a first glance, I thought that it was just something unusual and that at another try the tiny water drop would evaporate immediately. So I repeated the experiment three or four times. Each and every time the results were the same. Even more, When I maxed the heat from the bunsen burner, the droplet persisted more on the foil. It was absolutelly unbelievable. Now I had a problem. An explanation of the phenomenon surely existed, but it was somewhere lost in the mist and I couldn't see it at all. A couple of scenarios crossed my mind, but both proved to be wrong:

Maybe the aluminium in the foil turned by burning into Al₂O₃ that had a different thermal conductivity, and therefore, water droplets could withstand heat for a longer period of time, beacuse aluminium oxide transfered heat more slowly. But then, why did the droplet have almost sheprical shape? I mean, aluminiunm oxide is not a hydrophobic substance.
But what if the vaporisation process occured only where the water layer was thinnest? This meant that vaporisation could've given the droplet a spherical shape. But here lays another impediment. If vaporisation occured so fast, the droplet would have dissapeared instantaneously. So this is not the case!

As I had no other ideas, I posted the question on ChemicalForums.com. Thankfully, someone reminded me that this is due to the so called, Leidenfrost effect. "The Leidenfrost effect is a phenomenon in which a liquid, in near contact with a mass significantly hotter than the liquid's boiling point, produces an insulating vapor layer which keeps that liquid from boiling rapidly" - extract from Wikipedia. Image: Wikipedia In addition, the bigger the difference between the tempreratures of the two bodies, the harder does the droplet vaporise. Why? Beacuse the vapour layer under the drop is thicker, so it provides a better insulation. The vapour layer under the droplet litteraly makes the water particle float. This causes the particle to become almost spherical. So for now, I really know what happened there. I think this very interesting subject, that echoed through my head in the last two days, is worth studying in more detail with another occasion. See you next time!

No Sweet Sense for Sweet Cats

2009-10-18T18:10:00.020+03:00

We all like to eat sweet desserts; ice cream, candies, cakes, they're all part of our lives. The sweet taste is an ubiquitous element in all kinds of diets. And we, humans, are not the only lovers of sweet. Species from the Canidae family like the dog and its relatives also have an avidity for sweet foods, sweet being the indicator for carbohydrate rich edible things. Also, members of the Equidae (the horse and the donkey), Suidae (the pig), Ursidae (the brown bear - Ursus Arctos) amd other omnivourous species have the same tendency towards sugar.

However, not all animals are capable to sense sweet. Somehow, in the evolution process, a specific family of animals have lost this ability. It's the Felidae family. Little is known about the so called "big cats", such as the lion, the tiger or the panter. What is certain, is that the common cat (Felis Catus) is unable to detect the taste of even the most flavoured of sweets. It has been discovered that a deletion of an exon (coding part of the DNA) in the TAS1r2 gene is responsible for the loss of sweet taste in cats.

The deletion is marked in red. The numbers between brackets represent the exact number of nucleotides in each exon (the picture is adapted by me from the figure 2 of this article which I used as main reference).

Evolutionists say that natural selection didn't allow this taste to exist in cats because there was no need of it. The members of Felidae family are entirely carnivorous. The sweet taste allows omnivorous creatures to tell the difference between rich and poor carbohydrate food. But, because of the fact that meat of any kind is highly rich in these nutrients, there is no need for such a sense in cats. As a result, a mutation took place in this gene, taking out the unnecessary code, at a certain moment in the past.

Our cat on the fridge :-)

However, this certain moment is compuslorily subsequent to the swarving of cats from dogs, by reason of dogs manifesting a strong likelyhood for sweet. Personally, I think that humans may also have enhanced the dogs sweet sense as a result of the domestication process (so that the dogs have become almost omnivorous), but meanwhile, I'm sure that the contribution brought by humans in the development of canine taste senses is irelevantly small to be taken in consideration.

I would have also wanted to talk about a fellow gene of TAS1r2, the TAS2R38 gene (responsible for the ability or disability to taste PTC - a horrendously bitter chemical substance), but considering the length of the post, I'll do it with an other occasion (until then I would recommend you this wonderful book I'm reading: "When a Gene Makes You Smell Like a Fish"). See ya!

What Element Would You Like for Birthday?

2009-10-13T20:22:00.007+03:00

Today is quite of a special day, my blog turns one :D For making this day like so, I made an appraisement on 50 people, regarding the topic "What element would you like for your birthday>".

Besides naming an element I expected also a reason for choosing a certain element. Almost a third of the participants answered Oxygen, because it is crucial for life developement on Earth. On the second position was Hydrogen due to the fact that in combination with the element mentioned earlier forms water. With only four votes, Carbon is on the third position, as consequence for its ability to form an infinite number of organic compounds.

People also had spontaneous reactions some of which were very funny. As an example, one russian guy said Chromium because it is used for plating guns (a pretty weird answer). Others said that gold or silver would be the perfect options just because they are shiny. Last but not least, a woman let me know that she desires an element that she could put in her husbands food so that he would stop cheating her in love :)).

Personally, I would choose Manganese, as it has different colours from one state of oxidation to an other (Mn⁷⁺ is purple,2Mn⁶⁺ is green, Mn⁵⁺ is cold blue and Mn²⁺ is crimson red).

I hope you like today's post. See you next time!

Olynth Nasal Spray

2009-09-30T21:18:00.002+03:00

I have recently caught a cold. In the first days, apart from the sore throat sensation, my nose was totally congested, so I had to use a nasal spray. My option was Olynth. From curiosity at first, I read the list of components of this medicine. Then I thought I could find the way each and every of them acts to produce the general decongestioning effect of the spray and the way they are synthesized.

The composition of Olynth was: xylomethazoline chlorohydrate (the active substance), sorbitol (actually 1,2,3,4,5,6-hexanhexol), monosodium phosphate, benzalkonium chloride and disodium edetate.

The roles were the following:

Xylometazoline can stimulate adrenaline receptors. As a response, the organism will consider the stimulus to be actually adrenaline and capillary vessels of blood will constrict (vasoconstriction is one of adrenaline symptoms), not allowing blood to irrigate the area. The capillary vessels near the mucus secretion glands will not be activated, so the process of mucus secretion will stop. As a remark, due to the adrenaline mimetism capabilities, xylometazoline is not recommended for persons with heart diseases.
Sorbitol and the phosphate have the ability of retaining water (phosphate is a hidrate)
Benzalkonium chloride acts as an antiseptic. The disodium edetate is a preservative, useful for enhancing the action of benzalkonium chloride.

Synthesis

Xylometazoline has a pretty easy way of synthesizing, albeit it is not visible from the beginning if we are to propose a possible method for doing this. So, after trying to find by ourselves the synthesis, Otilia, Silvian and I, finally bumped into the method sketched in this book: Strategies for Organic Drug Synthesis and Design.
The benzalkonium chloride is produced by reacting N,N-dimethylbenzylamine hidrochloride with a haloalcane. The reaction occurs as following:
The next reaction, although not very difficult to understand, it intrigued me because NAD⁺ and NADH, present here in the synthesis of sorbitol, have too a major role in the glycolisis process. NAD⁺ is a substance made of ADP and a ribose (pentose).
For the symplification of the synthesis of sorbitol, I'll show only the part of the molecule implied in the reaction. As it can be seen, when NAD⁺ reacts with D-fructose, NADH and sorbitol are produced.
I'll end this post by showing the structure of disodium edetate and monosodium phosphate.

Disodium edetate Monosodium phosphate So next time you'll use Olynth, you will definitely know how it actually works and how it's made. See you next time!

My Summer Holiday - Bicaz Trip

2009-09-25T18:37:00.000+03:00

On the 26^th of July, me and my family started our family trip. We stayed at a floating hotel on the Bicaz Lake. The accommodation was pretty nice, and we had a great view of the lake from that point.

In the first three or four days we stayed at the hotel on the roof, getting a nice brown tan and also reading on chaise longues. Actually from this point of view, these eight days at Bicaz were really fulfilling: I have read Six Easy Pieces (R. Feynman), The Blind Watchmaker and A River Out Of Eden: A Darwinian View of Life, two books about evolution and natural selection from a very interesting perspective by the same author, Richard Dawkins.

In the fourth day, we went in a small trip around Bicaz Gorges and the Red Lake. When entering the Bicaz Canyon, the road becomes suddenly very tight. Rocky, vertical walls rise from both sides of the road and the Bicaz brook is on the right. It is extraordinary too see what such a small creek could have dug in millions and millions of years.

The Red Lake, a natural dam river, shaped in the form of an L, attracts many tourists, including us. A footpath surrounding the area is a great place to spend one or two hours walking. What is unique about this lake, is that pine stumps rise from the shallow water. Also, protected plants can be seen here on the edge of the track. For instance an endemic species of flowers, found only in Romania, Dianthus Callizonus, can be easily spotted here:

Dianthus Callizonus - endemic species of plants The Red Lake

As the fifth day came, we put on our sports shoes and reached the summit of Ceahlau mountain (Toaca Peak, 1907 m above sea level). It was a one hour hike from the base to a chalet at 1220 m high where we stayed and watched the scenic views and then went on climbing for another 2 hours and a half. Mainly, the track had a very steep angle but there were also plain bits of the footpath.

Me and my mom not being aware of the dozen kilometers path we were desiring to follow 'till the end of the day :D

We walked along the route for about an hour and a half until we found some benches to sit on. The place had a very spooky name "At the graves", but anyway we stopped to take a little rest.

Nothing to say, just watch

After another half an hour of hiking we stopped again (lazy us) at a place called "Cusma Dorobantului" (the soldier and his weapon), name inspired by the following piece of rock cutting through the sky.

Me on a pile of rocks

When seeing that the track leads us to a pasture, we were kind of relieved because we realized that this was the end, the so much desired peak. Although a splendid view was opening in front of our eyes, we made an idea of how much we still had to hike.

See that rocky peak? There we had to go

And as usually, when we finally were on the peak, the camera's battery died :)) . So sorry folks, but no images from the Toaca Peak today.

I leave the best subject for the next post: A Bulgarian All-Inclusive Experience.

NOTE: This post belongs to the series of posts "My Summer Holiday". The other post in this series is My Summer Holiday - The Olympiad.

Organic Chemistry Calculator

2009-09-24T17:43:00.002+03:00

It's been a while since I last used a free online tool for chemistry, that combines different aspects of organic chemistry, such as: structure, stoichiometry and general reaction mechanisms. But yesterday evening, while searching on the internet, I found a seemingly useful, free, online tool that definitely caught my eye straightway.

It was a quite complex software produced by professor Andreas Herrmann's team in the Polymer Chemistry and Bioengineering department at Groningen University. The software allows you to draw the structures of different compounds and put them in printable version, to calculate the ammounts of substance needed in different organic reaction processes containing up to six reactions. So, I consider it to be pretty useful. Its link is the following: http://chemist.hosting.paran.com/orgchem/

To test the efficiency of this software, let's try to synthesize an organic compound, for instance urea (the first organic compound to be ever synthesized), from inorganic compounds. Firstly, fill in the name of the reaction in the title section, in this case Wöhler Synthesis. In the structure drawing section, let's draw the structural formula of urea.

Click on the double bond tool and then click in the middle of the drawing field.

Select the Oxygen tool and click in one of the double bond's ends.

Now select the simple bond tool and double click on the other end of the double bond. By doing this, two simple bonds will appear connected to the double bond.

Select Nitrogen tool and click on each of the simple bonds' free end. Now, urea should look like this:

Now look at the proper calculator. You know that AgNCO + NH₄Cl → (NH₂)₂CO + AgCl is the reaction implied. In the starting formula cell, introduce the formula of AgNCO and in the product formula cell write the formula of urea ((NH2)2CO). By pressing the ">" sign near these two cells the molar masses will be automatically generated. As a starting amount of AGNCO let's take 100 grams, for example. After doing this, press again the ">" in the current cell. The number of moles will be generated this time. Because the equation is balanced with no coefficient, we leave the equivalent section untouched (the default value is 1). Now we can calculate the amount of urea produced by pressing "evaluate". If the result is 40.069389 then you have understood how to use this organic chemistry calculator. If not, re-read the tutorial and do exactly as told because I consider this tool very interesting and useful.

ChimeXpert International Chemistry Contest

2009-09-23T15:15:00.005+03:00

Hi there again! A few days ago, as I was talking to one of my friends, Victor (he also went to the same chemistry contests as me) on Yahoo Messenger, I realised that the registration phase for ChimeXpert International Contest has recently begun.

Chimexpert is an International Chemistry Contest, organised by Romania and hosted by Satu Mare every year. Up until now, students only from Romania, Italy and Hungary have participated, but this year the organisers intend to bring contestants from other countries too, so all and sundry is welcome.

In order to register for the contest you must first fill in an application form online and then pay a 12 euro tax (or 40 RON). You can find more information at the Regulation section, on their website.

About my personal experience with this contest, I can tell you that last year I participated at the International phase and returned home with a III^rd prize (as a result, after the proper competition I made a post about it). It isn't bad my result there, but I definetely know that I could have done better. Hope to see you there at this year's edition!

My Summer Holiday - The Olympiad

2009-08-27T12:20:00.044+03:00

It's a while since you last heard from me so let me tell you what I've done all summer long. To start from the beginning, I spent the first half of my holidays at home preparing for the Romanian National Earth Science Olympiad, then I went to the olympiad itself where I did pretty much nothing (but still gained some experience for the next years) and only then can I say that the proper holydays began (one week at Bicaz lake and two weeks in Bulgaria).

Brain Fitness - preparing for the Olympiad

Our holydays began this year on the 15^th of June, as usual. Due to the fact that I was qualified for the national phase of the earth science olympiad, I started my preparation from day one. The contest itself covered 4 major areas of science: geography, physics, chemistry and biology. For each of these disciplines, I had some reference books reccomended by my teachers Lidia Minza (chemistry), Dana Samoila (biology), Ion Cioroiu (geography) and Doru Costache (physics):

For biology, I have read some chapters focusing on ecosystems, biotope, biocenosis, food chains and more subjects like these, from an ecology textbook.
The physics covered only mechanics which is good, because it was my object of study at the physics class this year. The recommended book here were "Fundamentals of Physics, Volume 1" (Halliday, Resnick, Walker) and "College Physics" (Sears, Zemansky, Young).
Geography was a little bit trickier beacuse it implied a multitude of smaller domains such as climatology, hydrology, tectonic plate movement and a little bit of economic geography. Here, the reference books consisted in about 6 texbooks and one pretty old general meteorology course (Stoica, Cristea) for the first year students.
As for chemistry, the knowledge of basic inorganic chemistry would have done the job.

I know these domains of study do not seem to have many things in common, but it was our job to find connections between them because we had to analyse a problem from multiple views.

The Olympiad

The olympiad took place in Urziceni, a little town in the southern part of Romania. A funny thing about its history is that in the Middle Age it was called "Vai de ei" (translated into english as "Poor them" - well, it seems it is still the case today). So, on the 19^th of July, knowing that we will spend one week counting the hours until returning home, because of boredom (or at least this was what we thought), we packed our luggage and left home. When we arrived, we realised that our accomodation place was a high-school campus almost in the middle of the field, at about an hour away on foot from the town through the crops!... We had a catering room (the food was pretty good), dorms with 6 beds each (for boys and for girls separately), shared bathroom and showers (for both boys and girls - actually this was not bad at all :)) ). To sum up, the accomodation was pretty good with one exception:

A very "cute" cockroach fellow in our bathroom :)) The exams were really tough, combining geography, physics, chemistry and biology and it was very hard to analyse one problem from all perspectives. At the theoretical exam the highest mark was sadly only 63 out of 100. For the practical exam, the organizers took us on a trip to seven different landmarks, in order to observe the chemical and physical processes in each and every of these:

the water filtering station (the filtering processes by physical and chemical means should have been observed)

Here were the machines responsible for the first filtering step

the waterworks (here we should have kept our eyes on the purification process of underground water extracted from a 35 meters well)
the landfill (we should have compared and contrasted the ideal ecological landfill and the current situation of the dump site)
a natural gas compressor (here the chemical composition of the gas and the proper physical processing was the entire point of the visit - no photos here because we were put to sign a paper stating that the information unveiled here would remain confidential)
a dam over Ialomita river (the dam's functioning system was emphasized)

a bridge over the same river (erosion process highlighted here)

The bridge was somewhere in the left - not included in the photo because the purpose of the visit was not the bridge but the sedimantation/erosion processes (you can easily see the newly formed bank of the river as an extension of the land)

a field near Urziceni (we should have noticed the subsidence phenomenon happening)

So, from all the conclusions we had to make observing these places, we were given the practical exam. The subjects were not necesarilly difficult, but the lack of time was the major problem. We had about 7 subjects to solve in only 2 hours (and the solution for every subject was about two A4 pages long, so it was indeed a lot). After the exams, because it was very hot inside, we just took out all our matresses outside, in the schools courtyard, and staid awake till about 1:00 AM and only then, eventualy fallen asleep.

A poor quality photo (I'm the guy in green) - just wanted to show you the way we slept that night

But if you consider the life here to be peacefully and quiet, you haven't got the point yet. One night, as it was getting very late (about 1:00 AM) we went on the wrong street when returning home. Suddently, we realised that our route wasn't the good one, but too late, we all forgot the way of coming back. As it was not a good hour for knocking at people doors, we followed our intuition and went directly though the middle of a cornfield to the point where we thought our accomodation place was. After passing a railway line, a group of three weird looking, seemingly dangerous people came out of no-where. They started putting questions about where we were going, for what reason and things like that. Of course, being damn scared (we were only three boys and about four or five girls) we did not respond to them. Seeing no response from us, they started embracing the girls and trying to kiss them, knowing that we were defenseless. After a while they got bored seeing absolutely no reaction from us and left. With them going away from us, we were not only relieved, but we realised what could have happened in the worst scenario. Shall I be again in the similar conditions, I can tell you that I won't do the same thing again, that's for sure. I think you were used with photos from different moments, I know that, but I don't believe this was the right moment for a group picture, eh? :D

In the end, I came the 62^nd out of 85 (shame on me), but I think this year will count as experience for further contests and olympiads of this type.

Because the are so many things still to tell, I'll make two posts, one for each of other the two trips. So, coming soon... Bicaz Lake Trip and later, an All-Inclusive Bulgarian experience. :))

Petru Poni National Chemistry Competition

2009-05-28T21:52:00.001+03:00

Last weekend, I went to the national phase of a regional chemistry contest, named after the Romanian chemist Petru Poni. It took place at Onesti, a town near one of Carpathians' mountainous areas. We arrived there Friday morning and came back to Galati Sunday evening.

The contest consisted in a theoretical exam and a practical part, at which I scored 94 respectively 73 out of 100. In the end I won a Mention which is pretty good, though I could have done a lot better.

After the contest we enjoyed a walk in the mountains, we hiked along foot-trails and we saw some beautiful sights. Although it was a rather short trip, we liked it - a little escape from school ;-)

The team of my county on the top of a hill during the walk, I'm kneeling in the middle

To sum up my first high-school year, here are my chemistry results in competitions, so far:

43rd edition of the Romanian National Chemistry Olympiad, 1-8 February 2009, Arad - Honorable Mention
5th edition of the ChimeXpert International Chemistry Competition, 27-29 March 2009, Satu Mare - IIIrd Prize
7the edition of the Petru Poni National Chemistry Competition, 24 May 2009, Onesti - Mention

I hope the summer will bring both fun and better preparation for the next year chemistry competitions.

A redox reaction in ChemLab

2009-04-16T15:17:00.037+03:00

A chemistry laboratory isn't accessible to everyone, everytime, so I often use a virtual laboratory: Model ChemLab software (I have just an evaluation version and would be nice to receive some day a full/standard version). It's a pitty to find so few tutorials or resources on this product on the internet, so even the smallest contribution on the argument, counts. That's why my thought was to show some experiments made using this software. Let's compare a typical redox reaction (between KI, H₂SO₄ and oxygen) in the real lab vs. the virtual lab

In the real lab

The unbalanced reaction is:

KI + O₂ + H₂SO₄ → I₂ + K₂SO₄ + H₂O

The installation for making this reaction in the lab

In the Florence Flask we have KI solution. In one of the two tubes that enter the flask through the cork is pumped continously oxygen (or at least air), and from the other is carefully dripped out sulphuric acid. When a dark violet-blue precipitate is observed on the bottom of the flask, the acid stream should be stopped. Immediately after that, the solution will turn dark blue because of the solubilisation of I₂ in the liquid.

In ChemLab

After launching ChemLab, from the ChemLab Simulation Modules dialog, go to the Lab Wizards tab and choose ChemLab Wizard v1.7 (I run ChemLab v2.5 for Windows)

A reaction wizard will appear. Click Next.

Now complete the blanks with the Title, the Description of the reaction and the Author (your name). Then click Next.

The following step is to write the paths to the Introduction, the Procedure and the Observations files. Leave this blank, because it will help you only if somebody else will follow the instructions of the lab simulation you made. Only to mention. these three parts must be in ".RTF" or ".TXT" formats. So, click Next.

Select from the second list (Chemical Database) O₂, KI H₂SO₄, I₂, H₂O, the K⁺ cation and the SO₄^- anion and add them to the Added Chemicals list.

Select Potassium cation (K⁺) item in the first list and press Chemical Properties button. A dialog (Chemical properties:- Potassium Cation) will appar. Here you must follow a few steps:

Uncheck Stock Chemical, as you don't want to have potassium from the early beginning
Check Reaction Product checkbox
Check Flame Test Color, as you will recognize, using a burning droplet of solution, the potassium cation by it's pink-red flame colour.
From the color list, select the "Other" item:
A dialog (Color) will appear. Select the pink-red color and click OK
In the Chemical properties:- Potassium Cation dialog box, click OK

For SO₄^2- anion, I₂ and water, uncheck Stock Chemical and check Reaction Product.

For KI, check Solution and in the Molarity field write down 10M, because this is the molarity of the KI solution (pretty concentrated). As for the Flame Test Colour field, select that pink-red colour as earlier.

The same for sulphuric acid, but this time no Flame Test Colour.

Now, there is a little thing you must observe: ChemLab works only with liquids and solids, when talking about reactions. So, although it is practically impossible to dissolve oxygen in water, if we want to work with it, we will be forced to consider oxygen a solution (techlnically it would be possible if we cool enough the gas in order to make it a liquid - but this isn't our case).

All substances being added to the list, press Next.

It's reaction editing time! In order to do that, we first balance the equation by the redox method.

KI + O₂ + H₂SO₄ → I₂ + K₂SO₄ + H₂O

O₂^o --(+4e^-)→ 2O^-2....2.....1 2I^-1 --(-2e^-)→ I₂^o........4.....2

So the balanced reaction is:

4KI + O₂ + 2H₂SO₄ → 2I₂ + 2K₂SO₄ + 2H₂O

Now, that the reaction is balanced, we can start editing the reaction in ChemLab. Right-click on the Reactions node in the Reaction tree and press Add New Reaction.

A dialog will apear. In the Reaction Name field, fill in a name (for example, REDOX), then click OK.

Now, your window should look like this:

Drag one by one the substances from the right list to the left one. The Oxigen, the KI and the acid shall be the reactants and the rest of the substances should be the products.

When you add a substance to reactants/products another dialog is opened, asking about the coefficient of the substance in the reaction and a few other details. For example, for Oxygen put the coefficient 1 and click OK. For KI put 4, for the acid 2, for the potassium cation 4, for the sulphate anion 2, for the water 2 and for iodine it is 2. But when you are adding iodine, also check "In Solution", "Causes Colour Change In Solution" and "Uses Colour range". Don't forget to write down the minimum (0) and maximum (100) concentrations in the Low, respectivelly High fields. Select the blue colour from both two lists.

Now, that all substances have been added, your window should look like this. If so, click Next.

In the lab options window that you are facing now, check Include Metal Wire.

The next frame shows us an Add Indicator option; but because we don't need that now, we will just click Next.

The next frame shows a molecule viewer option. Skip it if you don't have molecular models for these substances.

The wizard is finally ready. All you need to do is to click Finish.

Now don't panic. After clicking Finish, it will show you 3 errors. On each and every of them click OK (these errors are caused by the absence of lab documentation files that we don't need for this demo).

Now we can start the simulation.

Take a 100 ml beaker (by right-clicking and then selecting Beaker, respectivelly 100 ml Beaker).
And here it is our Beaker.
Fill it half with acid (50 ml)
- Right-click and select Chemicals
- A dialog box will appear. Select the sulphuric acid and as a quantity, type 50 ml.
- The half-full beaker will look like this:
Fill an other beaker 1/4 with liquid oxigen (25 ml).
And an other one with KI (25 ml).
Take a big 250 ml Beaker and pour in it first the oxigen, second the acid, and third the KI solution (you can pour a substance into a vessel by placing the substance that will be poured above the vessel, right-clicking on the first container (that will be emptied) and selecting Pour/Decant).
After pouring the KI solution, the mixture should go dark-blue.

Sorry for the length of this post, but I wanted to pass through every step in order to make the entire virtual experiment clear. I'll also try, if you liked this, to make different experiments and describe them in ChemLab.

Bloody Chemistry

2009-04-05T20:32:00.017+03:00

As I was at Satu Mare, in the middle of the poster session, I saw a poster with a very interesting topic: fake blood, an application of chemistry in cinematography. When I returned home, I've made a little bit of research on the subject and here it is.

The fake blood effect

Fake blood is widely used in action films, thrillers, horror films and westerns. There are many ways to prepare fake blood but only one of them truly gives the impression of real blood.

Glassware you'll need: a beaker, a spatula, a watch glass and a hot plate
Chemicals you'll need:

Iron(III) Nitrate hydrate

Image from: http://www.huangchem.com/

Potassium Thiocyanide

How to do it:

Take one 100ml beaker and fill it up with KSCN solution.

Weigh about 2 grams of Fe(NO₃)₃ and carefully pour it into the watch glass. Put the watch glass on the hot plate and heat it up to 50^oC (actually 47.2^oC is the dehydration point of Fe(NO₃)₃, but 50 is just fine)
Now that the colour of the crystals has turned from intense magenta to light pink (or at least it should have), take using a spatula, a few crystals from the watch glass and put them into the KSCN solution
Now you should observe a deep crimson red colour in the solution as the result of the reaction

Fe(NO₃)₃ + 6KSCN → 3KNO₃ + K₃[Fe(SCN)₆]

Image from: http://www.buffalostate.edu/

Although it's sister K₃[Fe(CN)₆] is highly poisonous, this compound represents no threat to human health, so it is used in the film industry as blood which stains skin or in solid form it is used to imitate scars and so on. In western scenes you often see gun shots like they were true but in reality it's just a balloon full of K3[Fe(SCN)6] that will make you believe the bleeding is real.

Hope you aren't scared of that guy up there :)) It's just K₃[Fe(SCN)₆], you know!

Excessive water drinking really makes people fat?

2009-04-03T16:34:00.016+03:00

Some of you may have known that excessive water drinking makes you fat. Well, nutritionists and anatomists have been (and still are) in a continuous dispute on this topic. Personally, I consider this subject to be very interesting, because at a first glance the subject seems paradoxical.

What do nutritionists say?

Technically, water has no calories, so you can't deposit any of it's energy because it hasn't any (I remind you that this is energy from the burning of the nutrients). Its only use in the organism is that of being a very good transportation environment in the form of plasma in blood (blood plasma is more than 90% water):

It won't react with any of the nutrients that the organism needs
It is a polar substance that can dissolve all polar compounds and can transport as a suspension the apolar ones that won't normally dissolve in it.

So there would be theoretically no chance for you to get fat. Even more, if you drink cold icy water at 0^oC, your body has to warm it before putting it in the circulatory system. So 100g of water will consume 2 Cal, which means that it will even make you thinner (of course somewhere around zero point zero and a little bit grams, but hey it's weight loss wright? :)) )

What do anatomists say?

Except of the fact that water makes us gain weight simply by the weight of the water itself, there is a more profound explanation to be found at a much smaller scale, the cell level.

It is known that a cell's membrane is a phospholipidic three layered tissue which is composed from membranous units. A unit has both a hydrophobic and a hydorphilic head. This maintains a constant concentration in water of the cytosol between 60-70% as far as I can remember from biology classes. When the concentration in water of the cell belittle under these values, some proteic tubes are opened in order to let the water in. The same happens when the difference between the outside and the inside is pretty significant (the outside is richer in water in this case).

If a person drinks a lot of water regularly, the blood plasma will be always very rich in water, so cells will receive continuously water, until the interior concentration will equal the exterior concentration. Like a rubber gum, if maintained elongated for a long time, the cell membrane will lose its elasticity and suffer plastic deformation. From this point, the cell membrane can't regain its initial shape and will occupy a larger volume. That's the story for a single cell. But when the measuring unit is several billion cells ( around the number of the cells in the human body) they will have a considerably bigger volume, and will give the impression of a fat person.

So, next time don't put the blame on hamburgers for all the fat. Blame water :)) !

ChimeXpert International Contest

2009-04-01T15:08:00.016+03:00

Last weekend I participated at the 5th edition of the ChimeXpert International Chemistry Competition, which took place this year at Satu Mare. Even though I've obtained a III^rd prize, I am pretty disappointed with this result because I was really close to the second prize. The competition itself consisted in two parts: a three hour written test and a poster presentation in no more than three minutes. I chose the carbon nanotubes as topic for my poster, a fascinating subject that I have researched browsing these books as much as my understanding level allowed me: "Understanding Carbon Nanotubes: From Basics to Applications" (an advanced book, but full of applications; this book helped me to form a practical perspective on the argument), "Science of Fullerenes and Carbon Nanotubes: Their Properties and Applications" (it talks a little about nanotubes but describes very well their special properties) and "Handbook of Carbon, Graphite, Diamonds and Fullerenes: Processing, Properties and Applications" (it helped me figure out how carbon nanotubes are produced).

And now, some photos from the competition:

Me coming through the hallway

All seven of us from Galati county at the official opening of the competition (in the third row)

Hungarian folk dance was a nice show after the opening ;)

The classroom where I sit the written test (I am in a white shirt in the back of the photo)

Me and my poster

After the competion, in our hostel-like room

After two days of competition, 1000 km from home, we returned to Galati. It was pretty nice that everybody from our county returned with a prize, whereas contestants from other counties returned home empty-handed. Lucky us!

Romanian National Chemistry Olympiad and ChimeXpert

2009-02-17T19:38:00.007+02:00

Hi! In the last three weeks I hadn't much spare time because I've participated in two chemistry contests, one of them being the Romanian National Chemistry Olympiad, from where although I've returned with an Honorable Mention, I still can feel that I could have done better.

The team members from my county (all seven of us) in front of the Palace of Culture in Arad, just after the ending ceremony (I am at the leftmost).

The other is ChimeXpert, an international chemistry contest (well, just Romania, Hungary and Italy will participate this year) in which I've qualified for the last phase, the international one. It will take place on 27-29 of March, in Satu Mare. Here I will take a written test that is worth 60% of the total mark and I'll have to present an original paper about applied chemistry (this part values 40% of the final score). So for this, I'll research for some interesting information and definitely try to use some creativity.

The Manganese Rainbow

2009-01-28T18:24:00.010+02:00

As you may well know, manganese salts are generally black or gray. At the first sight manganese salts do not appear to be very interesting. But at a closer look, this element won't appear so boring. Actually, I can easily say that this is one of my favourite elements for some of its particular reactions. Yesterday, while illustrating redox reactions, I had the opportunity to make one of manganese's most fascinating experiments.

The first two attempts went totally wrong, and when I was on the verge of succumbing my positive state and just give up, the farewell try went just marvelous. It's a very coloured experiment that you definitely shouldn't miss.

Glassware you need: one 100 ml cylinder; one 600 ml beaker; stirring rods; a burete.

Chemicals you need: 500 ml NaOH 6M; H₂O₂ 0,1% (you can obtain it by dissolving 1 ml of pure H₂O₂ into 350 ml water); CH₃COOH 6M; 0,05 g of KMnO₄ dissolved in 1 ml of water and ice

How to do it: in the NaOH solution chilled at 0^oC the entire quantity of permanganate is dissolved. Then from the burete 1 ml of H₂O₂ is added under continuous stirring. We can clearly observe now a palish green colour, because of the MnO₄^2- ion. The reducing agent is H₂O₂.

2Mn⁷⁺O₄^-_(aq) + 2HO^-_(aq) + H₂O₂ → 2Mn⁶⁺O₄^2-_(aq) + 2H₂O + O₂

You continue both adding H₂O₂ and stirring the upper layer of the substance until it gets cold blue.

2Mn⁶⁺O₄^2-_(aq) + 2HO^-_(aq) + H₂O₂ → 2Mn⁶⁺O₄^3-_(aq) + 2H₂O + O₂

On the top you should add now the CH₃COOH, slowly and continuously stirring. Around 20 ml would be more than enough. A crimson red colour should be now observed due to the reaction between the hydronium and the trivalent permanganate ion previously formed.

In the end it should look like this:

Tips:

Use only chilled NaOH
Do not use indecorous proportions of the substances! Follow the gravimetric instructions as close as you can for an accurate result.
When you mix, try to mix only the upper layer in order not to spoil the colours.
Have fun doing this!

Persil, an inorganic detergent

2009-01-27T17:26:00.009+02:00

Hi there again! I have indeed said that I will no longer post until the Chemistry Olympiad, but today while looking at a video about the chemical element Boron, I heard the fact that Persil is an inorganic detergent that has his name inspired from its two main compounds : sodium PERborate and sodium SILicate. So I did a little bit of research on the Internet and may I say that, I've found some pretty worth to mention things.

As I said earlier the two principal compounds of Persil are sodium perborate and sodium silicate. The major role of the perborate, in the washing process, is to decompose at high temperature in the washing machine in the presence of water to form hydrogen peroxide, and a B(OH)₄^- ion. In the next step, the hydrogen peroxide will remove the stains by oxidizing them and making them more soluble into the hot, boiling water.

A little bit of History Before the first world War, there were no detergents commercially available. Women had to wash clothes with house made soap in the water of the nearby river (only rich people could afford their water pumping system).

Image from http://www.hohenstein.de/en/index.asp

So, in 1907 Henkel started to commercialize the first detergent which was named after the two major components. This was to be one of the revolutionary inventions at the beginning of the XX-th century. But its great success wasn't felt immediately. Many people couldn't afford it, and it became popular only after the First World War, because it was widely used to wash the soldiers clothes. So only after that 4 years Henkel could lower the price in order to make it accessible to most of the people.

Original advertising poster

Nowadays, Persil is one of the very few toatally inorganic, commercially available washing products left on the market, that is widely used in Europe; the situation has pretty much changed in the last 100 years.

See you next time!

The Romanian National Chemistry Olympiad

2009-01-13T17:01:00.010+02:00

Hi there again! Sorry for not writing for more than 2 weeks now, but I have been very busy with the chemistry Olympiad two Saturdays ago. I can say that I am very happy with my result, because I've managed at this point to qualify at the Romanian National Chemistry Olympiad, which takes place at Arad this year.

Because of the fact that the Olympiad is so close, and I have to learn a lot of new things in just 1 week, my chemistry teacher, Lidia Minza, gave me a few days off from school, in order to exercise some high-level problems, and to revise both theoretical and practical key aspects of Inorganic Chemistry, also mentioned in the Syllabus for the Olympiad.

So, see you after the Olympiad!

ChimeXpert Contest, First Phase

2009-01-03T21:58:00.004+02:00

Today I have seen the results for a chemistry contest I have participated in. The contest is called ChimeXpert and it is an international contest, organised by Romania (you can participate by registering at this link http://www.chimexpert.ro/index.php?id=29&L=2 and paying a fee of 12 Euro)

I've taken 247.5 points out of 300, which means that I correctly did 82.5% of the whole test. I was positioned first in my county, Galati, but I am pretty dissapointed because I have had higher self-expectations. Although my place in the county ranking may sound good, in the national classification I am only the 107th out of 282. In other words I am situated in the first 37.94%. I want to congratulate my classmate Andreea Stroia who obtained the same result as me.

The contest has taken place on-line, without a certain timebound and that means that participants could collaborate between them and even teachers could solve the problems for the participants. Even more, around 5% of the problems have been asked, in my and my teacher's opinion, wrongly (with none of the options correct - it is a 5 given options from which only one is correct test).

Now it is certain that I will pass to the next phase, but if I want to go to the international phase, I have to prepare myself a lot more because only the first 10% of all participants will pass.

With this post I invite anyone interested in Chemistry to participate in the following years, in order to make this contest truly international (I think many of my readers are high-school students or teachers).

New Year Chemistry

2009-01-02T16:23:00.018+02:00

Happy New Year to All! I am going to talk in this post about Fireworks Chemistry, a very interesting subject may I say, with lots of Redox equations and thermal decompositions.

Image from http://www.photoshopessentials.com/

You surely have observed that fireworks are coloured in different ways: yellow, green, red, blue, purple, white and even more colours. A specific colour is produced when a metal or one of the metal's salts is burned into the air violently. In this way one metal or any of it's salts at the same oxidation state give the same colour which can be described as following, as a result of a very common flame test.

Element	Flame Colour
Li⁺	Crimson red
Na⁺	Yellow
K⁺	Violet
Ca²⁺	Orange Red
Sr²⁺	Red
Ba²⁺	Dirty Yellow
B^3-	Green
Cu²⁺	Green

Video from: http://www.youtube.com/user/mrericsully

There are 2 characteristics of fireworks that are worth to be mentioned:

Incandescence (light produced by heat)

Substances like Magnesium (powerful white light) or Strontium (crimson red light) need a lot of heat in order to be put on fire. So a longer time is needed by these substances to catch fire. On the other way, there are substances like some Barium salts that are unstable even at room temperature. In order to synchronise the explosions of the substances with high igniting temperatures and of the substances with higher instability some metals like Aluminium, Magnesium or Titanium are added.

Quality

Sodium particles can contaminate fireworks so they will have a dirty yellowish shade. For this not to happen, MgO is added to the fireworks (it won't react unless there is some sodium). Also a very important aspect of fireworks' quality is the smoke: If too much is generated, the colours will be spoilt.

Generally, nitrate salts are used for fireworks, due to their instability, and light weight. For the igniting mechanism, phosphorus is preferred. Also, when we talk about fireworks there are two main igniting systems: in steps and all at once. Both need an initial explosive in order to make salts burn and after that shine is diverse colours. This substance is generally an ammonium salt due to it's instability and explosive properties.

A two step igniting system

Of course, what I presented is only a very vague description of the phenomena, because I didn't include reactions or more complex diagrams, in order just to create a general impression about the subject. I can only now wish you again a Happy New Year!

Answer to: A mind snapping quiz

2008-12-28T15:19:00.011+02:00

Two weeks ago I posted a quiz about a reaction that I considered interesting. Its text is the following:

You have some chlorinated water. To the solution you add some sodium nitrate, but not in stoechiometrical amounts (the sodium nitrate is fewer than it is necessary to react entirely with the mixture). The reaction products shall be:

Sodium hypochlorite and nitrogen dioxide
Nitric acid, hydrochloric acid, hypochlorous acid, kitchen salt and sodium hypochlorite
Sodium hypochlorite, hydrochloric acid and NO2
Nitric acid, sodium hypochlorite, hydrochloric acid, kitchen salt and hypochlorous acid
Kitchen salt, oxygen and hydrochloric acid

From the early beginning we can see that we have "chlorinated water". This means, that when we bubble chlorine into water the following reaction can be observed:

Cl₂ + H₂O → HClO + HCl

Next, we pour some NaNO₃ into the solution. This means that the hypochlorous acid (HClO), and the hydrochloric acid will react to form nitric acid and sodium salts:

HClO + NaNO₃ → NaClO + HNO₃ HCl + NaNO₃ → NaCl + HNO₃

Because of the fact that the initial mixture is in excess, in the final solution will remain HClO and HCl too, but not even a drop of NaNO₃.

To sum up the compounds of the final solution will be :

HClO
HCl
NaClO
NaCl
HNO₃

So the correct response is the fourth variant

I have seen that only 5 persons have answered to my quiz (from which only one of them has responded correctly), although I had expected a lot more to react. I know that this may be explained by the Christmas period that we are passing through, and people are more implied in celebrating this event in family than looking on chemistry blogs :-), and also by the fact that my blog is pretty new and hasn't got many followers yet. Merry Christmas and a Happy New Year!

Hydrogen Peroxide and Ozone

2008-12-26T14:37:00.010+02:00

Three days ago, while I was reading an article about Oxygenated Water (H₂O₂) and Ozone (O₃) chemistry, I saw 3 different reactions between the same substances mentioned above, all three possible. The reactions were:

2H₂O₂ + 4O₃ → 2H₂O + 7O₂
H₂O₂ + O₃ → H₂O + 2O₂
H₂O₂ + 3O₃ → H₂O + 5O₂

I let the book down for a minute and asked myself why: "Why all three reactions are possible?". Immediately, I realised that the first one is the sum of the last two; so, all I had to do is to prove the last 2 reactions.

H₂O₂ + O₃ → H₂O + 2O₂

RedOx Method

Firstly everything went wrong. I thought that the oxygen atoms in the H₂O₂ molecule have the oxidation state number -2, but after a little bit of documentation I had found that, due to it's allotropic state, oxygen in H₂O₂ has an N.O. of -1 .

OK. This wasn't a problem any more. Then, i noticed that O atoms are both the oxidizers and the reducers in the reaction (Nothing new, of course. There are such reactions, in nature, where the same element is both reducer and oxidizer; for example H₂SO₄ + S → SO₂ + H₂). In conclusion the partial ionization reactions are:

O^-1_(H₂O₂)—( -1e^- )→ O⁰_(O₂) O⁰_(O₃)—( +2e^- )→ O^-2_{(H₂^δ+O^δ-)}

Separate Decomposition Equations Method

So we have:

H₂O₂ → H₂O + 1/2 O₂

O₃ ↔ 3/2O₂

————————————(+)

H₂O₂ + O₃ → H₂O + 2O₂ (→TRUE)

H₂O₂ + 3O₃ → H₂O + 5O₂

₃

₂

From these two we deduce that the first one is also plausible. And that's it: All three are true!

An illusiory paradox

2008-12-22T21:41:00.004+02:00

Because the Chemistry Olympiad is on 10 January and there is very little time left, I use the winter holidays for training myself for the Olympiad. It was 11 o'clock and I was solving problems from a collection of more complex exercises, when my attention fell on one entangled question. It said: In a closed recipient heated at high temperature, ŋ particles are introduced (ŋ is a natural number). In the same conditions are introduced ŋ particles more, and it is observed that the pressure remains the same. Explain the phenomena. The first thing that crossed my mind was the ideal gas equation PV = ƞRT. This meant that the pressure, and volume remained the same, so the temperature lowered. But immediately I saw the part of the text that stated that the conditions remained the same. I had no inkling for, let's say, about half an hour, although I was endeavoring to find the explanation. Finally I gave up. I looked at the answers part of the book and what I saw shocked me by it's unexpected simplicity We know that the pressure depends on the number of collisions of the recipient's wall with the particles. That means that if the pressure is constant , we have the same number of particles (in the same conditions). You may say now: "What? But we can't have the same number of particles because we added more. It's a paradox!". Yeah! You're half right, but you neglected a very important aspect of chemistry. Particles react with each other. Nobody told you that the particles we introduced the first and second time were of the same type. So here's the explanation: The first particles (A) reacted stoechiometrically (they were echimolecular) with the second set of particles (B) as following: A + B → AB. We had initially ŋ particles, we added ŋ particles, and in the end we had ŋ particles. The simplest reaction model of this type that crosses my mind is Mg + S → MgS.

A mind snapping quiz

2008-12-14T18:37:00.010+02:00

Hi. Sorry for not being active for such a long period but I had to give my exams. Today I shall propose you a chlorine reaction related quiz:

You have some chlorinated water. To the solution you add some sodium nitrate, but not in stoechiometrical ammounts(the sodium nitrate is fewer than it is necessary to react entirely with the mixture). The reaction products shall be:

sodium hypochlorite and nytrogen dioxide nitric acid, hydrochloric acid, hypochlorous acid, kitchen salt and sodium hypochlorite sodium hypochlorite, hydrochloric acid and NO2 nitric acid, sodium hypochlorite, hydrochloric acid, kitchen salt and hypochlorous acid kitchen salt, oxygen and hydrochloric acid

view results

UPDATE: I have posted the answer followed by the explanation at the following post http://dailychem.blogspot.com/2008/12/answer-to-mind-snapping-quiz.html

Black Smokers

2008-11-23T20:35:00.008+02:00

You may have heard hypotheses about the existence of some lifeforms under the thick ice crust of Europa, the smallest Galilean moon of Jupiter . It is believed that under the heavy shards of ice, lays an ocean steaming of life, heated by . submersed geysers. But it's just another theory. On earth, these underwater geysers are called Black Smokers and are to be found on the floor of the oceans. They are eliminating a very hot, homogeneous mixture of water, in both vapour and liquid state (it is called super-critical fluid). Also they give away metal particles that have been ionized by the very high temperatures in the Asthenosphere Layer (the magma layer).

image from: http://www.dgukenvis.nic.in/

How it works

The ionization reactions that take place in side of this "furnace" can be described as in the following series:

The hot, glowing magma in the mantle with a temperature varying from 700⁰C to 1300⁰C, is right under the sea bottom.
At these temperatures the electronic layers of metals and non-metals , especially the high energy layers, become unstable, so electrons may go from one particle to another.
So metals will give extra electrons in order to form a stable structure, and non-metals will accept electrons for the same reasons.
The reactions which take place here are described here (the diagram couldn't fit in the size of the page and if made smaller, you couldn't understand anymore what is written without a magnifying glass )

Ecosystems

Although life is very hard to find at these depths, black smokers are incredibly the center of entire ecosystems. Sunlight doesn't reach these depths, so many organisms — such as archaea and extremophiles — convert the heat, methane, and sulfur compounds provided by black smokers into body energy through a process called chemosynthesis. More complex life forms like clams and worms phagocytate these creatures. The most primitive organisms that live here also deposit minerals into the base of the black smoker, therefore completing the perpetual cycle of life.

Lysozyme - Antibacterial Enzyme

2008-11-19T22:27:00.000+02:00

During a biology class, we talked a little bit of the enzymes that protect our body from bacteria. Lysozyme is one of them. I remembered from an other class two years ago that this substance is to be found not only in saliva but also in the other secretions of the human/animal body. My teacher disagreed with me and I insisted. So we did a little research and what we found was more than surprising.

Lysozyme is a rather large category of antiseptic enzymes that damage the bacteria by hydrolysing with their cytoplasm and effectively destroying it.

Lysozyme crystal - electronic microscope Image: Wikipedia

It can be found in a series of secretions of the human body such as tears, milk, saliva, blood, mucus, sweat.

Whereas the skin is a protective barrier due to its dryness and acidity, the conjunctiva (membrane covering the eye) is instead protected by secreted enzymes, mainly lysozyme and defensin. However when these protective barriers fail, conjunctivitis results. From the failure of the protection by lysozyme of other conjunctive tissues Salmonella can result.

Salmonella Bacteria - Wikipedia

Batteries - How could we live without them?

2008-11-18T19:26:00.000+02:00

Mobile phones, Ipods, Mp3-players, digital cameras, a cars engine all are using batteries. But what you mightn't know is that not all batteries are of the same type, in other words they use different substances. The first battery was invented in 1800 by Alessandro Volta. He created a series of copper and zinc coins, and between each layer a wet salty piece of carton. The first model wasn't able to drain a big amount of energy. From then a lot of battery types have been invented but I will only talk about two of them: The Galvanic and the Planté Electric Cells.

The Galvanic Cell

Image : Wikipedia

For this cell it is used one electrode made of copper (submersed in a bath of copper sulfate) and one made of zinc (submersed in a zinc sulfate solution), interconnected by a bridge of salt (ex: NaNO₃). At this point the reactions can be described as the following:

At the anode we it will see that zinc bar is thinner and thinner because of the reaction: Zn⁰ → Zn²⁺ + 2e^-
At the cathode the copper bar widens so more and more copper is formed: Cu²⁺ + 2e^- → Cu⁰↓

The global reaction (current generator) is Cu²⁺ + Zn⁰ → Zn²⁺ + Cu⁰↓

It is conventionally represented (-)Zn l (s) Zn²⁺(aq) ll Cu²⁺(aq) l Cu⁰(s)(+)

The Planté Cell

It is the rechargeable battery to be discovered, and it is special because uses only one metal: Pb. It was discovered in 1859. Despite having the second lowest energy-to-weight ratio (next to the nickel-iron battery) and a correspondingly low energy-to-volume ratio, their ability to supply high surge currents means that the cells maintain a relatively large power-to-weight ratio. These features, along with their low cost, make them attractive for use in cars to provide the high current required by automobile starter motors. The reactions are:

Pb (s) + SO₄^-2 (aq) → PbSO₄ (s) + 2e^-
PbO₂ (s) + 4H₃O^-(aq)+ SO₄^-2 + 2e^- → PbSO₄ (s) + 6H₂O (l)

Practical cells are usually not made with pure lead but have small amounts of antimony, tin, calcium or selenium alloyed in the plate material (from which the electrodes are made of)

Synthesis of interhalogenary ICl3

2008-11-13T20:28:00.000+02:00

Today, while I was searching for some interesting chemistry questions on Chemical Forums, I found one very interesting question that caught my eye. Its text was the following:

How does powdered potassium chlorate, powdered iodine and the dropwise addition of HCl in a water bath go, in order to synthesize ICl₃?
What does ICl₃ decompose to ?

After thinking a while, I realised that the process can take place only in a few steps. We know that halo-oxides in reaction with diluted hydrochloric acid generate interhalogenary compounds such as the ICl₃.

In our case the two reactions are described such as following:

5 KClO₃ + 3 I₂ → 3 I₂O₅ + 5 KCl
I₂O₅ + 10 HCl → 2 ICl₃ + 5 H₂O + 2 Cl₂ ↑ (in aqueous solution)

In order to answer to the second question I've looked up in in a chemistry textbook in Romanian and I found out that 2 ICl₃ → 2 ICl + Cl₂ ↑.

Energy without energy?

2008-11-10T20:00:00.000+02:00

Today when I was sitting in front of the TV like a couch-potato watching a quantum mechanics documentary film on Discovery Science, I suddenly remembered a very interesting question about the physics of the electron: being given the reaction e^- → e^- + γ how could you apply the energy conservation principle knowing that both the photon and the electron resulted have each the same energy as the electron which entered in the reaction?

From the beginning you must know that we must apply the uncertainty principle : Δt • ΔE≥ ћ, so the time elapsed multiplied by the energy of the specific particle isn't less than the momentum of the particle at a specific time. In other words when we know the energy of a particle we can't know the momentum. All quantum particles are obeying to this law, known as Heisenberg's law.

From these lines above we must realize that both the energy of the photon and the one of the electron are smaller than ћ/Δt. For the precedent case to take place we must admit that the life of γ is smaller than ћ/ΔE. From tables describing quantum numbers we can see that the value of the particles momentum (ћ) tends to zero (infinitesimally small) while the energy of the same particle is pretty big (measured in MeV - mega electron-volts). The conclusion will be that Δt represents an extremely short period of time (around 10^-23 seconds). When scientists found that answer they (as you might have done) asked themselves "What? Is that even measurable, and if it is has it got even the smallest relevance to the surrounding world"? The answer was yes. It really has phenomenal relevance to everything in this world, but at a very small scale, dimensionally speaking. How? Well, you may know that in the electron shell electrons are keeping each other from tearing apart from the atom not only by electromagnetic forces, but also by a special property of electrons recently discovered by scientists. When you put 2 electrons together they won't rush out of each others way as you would expect, but instead of that, they would stay at a safe distance from one another, big enough to explain the repulsion between the same polarity charges, but small enough to be considered a sort of attraction. Now I know you are asking yourself "But how could that be possible by normal physico-chemical properties?". Well, normally it can't. But remember the decomposition of the electron I talked about earlier? In this context it means that when the first electron (let's simply call it A) feels the presence of B (the second electron), it will immediately emit a photon that will rush towards B (in that very small amount of time) and when there, it will take place the opposite reaction e^- + γ → e^- . So next B will emit the photon to A and so on. To visualise this imagine a tennis match it is quite the equivalent (the two players are A and B, the ball is the photon). To sum up, the γ has so a short life that in the first reaction can as well be omitted. A second argument will be that adding the two opposite reactions described you will remain with e^- → e^-.

How could the piezoelectric phenomena be explained?

2008-11-09T16:31:00.001+02:00

Reopening my chemistry question-answer notebook, I found one interesting question which had stayed in my mind for two or three months during springtime at the beginning of this year. It sounded like this: How could the piezoelectric phenomena be explained by phisico-chemical properties of crystals? Even if you imagine that I simply abandoned it after this pretty long period of time, I eventually found the answer. Firstly, you must know that these special properties are applied to ~~only the~~ Ionic Crystals (a rather large category in the world of salts).

In order for an electic impulse to be generated in a series of attempts using piezoelectric crystals, you must put presure on the crystal. Doing this, the reversed polarities will come in the immediate vicinity on the brink of contact between the two oposed charges. If the limit is surpassed the negative and positive charges will try to equilibrate so as in the following sequence:

Firstly the spare electron on the negative charge will try (as usual) to escape the ionic negative trap.
So, when it finally founds the pozitive charge with some free orbitals left, it will imediately jump to the positive ion.
This process will repeat and the electron we are talking about will depolarisate everything in its path.

A powerful remark would be that the crystal will vibrate if put unter elctrical curent. This fact has deep conseqences. Right now as you may listen to some music or something else, a tiny quartz crystal frenetically vibrates in your PC's audio system.Those crystals are used in the other way for microphones, precise vibration equipament and the list may continue.

Even if I can rather say that my expectations were those of a more complex demonstration, it nevertheless satified my curiosity and, may I say, gave me a 30,000 feet overview of the concept.

Video from my channel on youtube http://www.youtube.com/user/andrewwwstube

UPDATE: Thanks to Ψ*Ψ, I corrected the post: indeed, the piezoelectric effect is applied not only to ionic crystals but also to some organic compounds, such as the polyvinylidene fluoride.

The abnormalities of the first and second period of the Mendeleev's Table of Elements

2008-11-09T16:13:00.000+02:00

Two or three days ago, when I was reading an article in a book, I saw a very interesting thing about the similarities between an element and another in the immediate lower right vicinity of the first one (small diagonal similarities).

Anomalies in the second period Even if we talk of alkalii metals, we can see that between them, there are rather significant differences. For example: two molecules of lithium hydroxide decompose at high temperature to form lithium oxide and water, while sodium hydroxide doesn't decompose. In the same manner two molecules of sodium hydride decompose to form two atoms of sodium and one molecule of hydrogen, whereas lithium hydroxide doesn't. Thanks to the small atomic volume of lithium and of its high electronegativity (in comparison to sodium), its salts are unstable for example: two molecules of lithium acid sulfide decompose at high temperatures in order to form lithium sulfide plus hydrogen sulfide. In the same way, at high temperature, lithium carbonate decomposes resulting from the reaction lithium oxide and carbon dioxide. To sum up, lithium resembles more to magnesium than to sodium. As a final example I shall say that lithium, at room temperature and normal pressure (standard conditions), reacts with nitrogen forming lithium azide. In the same way magnesium reacts in the same conditions with nitrogen forming magnesium azide. We can observe that not only lithium resembles on diagonal with magnesium, but also Berrilium has certain similarities to aluminium, Bohr to sillicium, carbon to phosphorus, nitrogen to sulfide and oxygen to chlorine.
Anomalies in the first period I left this concept at the end because hydrogen (the only active nonmetal in the first group) resembles equally to alkalii and to halogens. The positive ion of hydrogen (which actually is the proton) takes the electronic configuration of alkalii and it forms a kind of hydroxide: water (H-OH), but it doesn't exist in this state, set free, in nature. Another argument against the resemblancy of the proton with alkalii is that the positive hydrogen ion is 100,000 times smaller than the lithium ion. The negative ion of hydrogen has the configuration of halogens and also a polarization tendency. As halogens do, H- forms salts with alkalii, but the ionic radii of H- is almost equal to the ionic radii of iodine. The explanation of this phenomena is that only one proton can't control at the same time two electrons which are repulsing each other. Therefore, the ionic volume of H- increases.

Video from my channel on youtube http://www.youtube.com/user/andrewwwstube

No Hemoglobine for Crabs

2008-10-25T21:02:00.000+03:00

Today, during a break, I went to The Periodic Table of Videos site ( a site containing a video about each and every chemical element found on Earth - very interesting though) and I saw the one about iron. There it's mentioned "Iron is an absolutely central element to life...". OK, you will say: That's nothing new to me! But what's just after this, shocked me: "... except for crabs which use copper". So, I made a search on the Internet and what I found, turned out to be even more interesting than the fact itself. You must know that at life's beginning in the oceans, when trilobites (crabs included) first appeared, Panthalasa (The planetary Ocean) was a cold and hostile environment for leaving. In these conditions oxyhemoglobine dissociates so it is impossible for it to carry oxygen. So trilobites have come with an ingenious solution. They used a rather complex cell containing a protein (hemocyanide) which could ease the transport of the oxygen in blood. The hemocyanide contains two central copper atoms instead of the four central iron atoms and it takes 10000 atoms to carry only one oxygen atom, whereas in the hemoglobin only 8000 atoms are needed to transport 4 oxygen atoms. As a curiosity, blood with hemocyanide, when exposed to the air turns in a bluish colour because of the oxidation of hemocyanide to oxyhemocyanide in the reaction 2HC + O₂ = 2(HC)O where HC is hemocyanide and (HC)O represents oxyhemocyanide.

Image: Heinrich Harder from Wikipedia

Now going up 300 million years into the future from that distant point in the past, we can see that we arrive in the present. Only few species have conserved this old way of oxygen harnessing, the whole rest adapting and making things more efficient day by day.

Image from Wikipedia

Literally Strange Particles and Their Behaviour

2008-10-24T18:46:00.001+03:00

Some time ago, I told you that in the nuclear physics chapter from "The New World Mr Tompkins" I had read about miuonic/electronic neutrinos . I think that an equally interesting part of the book is the one dedicated to the strange particles. What I found there didn't satisfy my curiosity, so I went again to Natalia Fiuciuc's book "In Lumea Atomului".There, the information was based on the idea of defining this kind of particles and to describe the basic property of strangeness. Strange particles are subatomic particles that are generated in very strong interactions (ex: disintegration of protons), and are always disintegrated in weak interactions. The property that defines those particles specific character is called strangeness, which corresponds to a quantum number from 3 to -3 . But I still haven't answered to a very important question: Which of the particles have a powerful strange character? Well, there are basically 2 types of corpuscles that manifest in this way. The first group is the meson type, especially Kaons (K) and the η meson. The second major class is the hyperons (Λ⁰, Σ⁺, Σ^-, Σ⁰, Ξ^-, Ξ⁰, Ω^-). Before some nuclear reaction equations I will mention you the three laws of the strangeness conservation:

The strangeness quantum number always remains the same during strange particles generation.
Strange particles are always generated in pairs (not necessarily the same strange particle)
The quantum number never remains the same during strange particle disintegration.

So let's take in consideration the following 2 examples:

p + p → Σ⁺ + p + K⁰ So the strangeness equation will be 0 + 0 = (-1) + 0 + (+1) ↔ 0 = 0 (True because it is a generation of particles & the strangeness is conserved) → The reaction will take place.
Σ⁺ → p + π⁰ So the strangeness equation will be +1 = 0 + 0 ↔ 1 = 0 (true because it is a strange particle disintegration & the strangeness isn't conserved) → The reaction will take place.

I consider these particles interesting, because they are the exception to the rule of the conservation of quantum numbers, in this case the strangeness.

The Bessemer Converter 2

2008-10-20T19:57:00.001+03:00

Today I have found this very interesting article about the Bessemer Converter in The Sheffield Industrial Museum: "The Bessemer Converter at Kelham Island Museum is one of only three converters left in the world. It was used by the British Steel Corporation in Workington until 1975, and was brought to the Museum in 1978 as an example of the revolutionary steel making process which first took off in Sheffield. The Bessemer process, patented by Henry Bessemer in 1856, converted iron into steel" (actualy they have put the 2 steps: converting iron into steel by recycling it in the converter and then transformation of the pure iron into steel in just one step . The egg-shaped converter was tilted down to pour molten pig iron in through the top, then swung back to a vertical position and a blast of air was blown through the base of the converter in a dramatic ‘blow’. Spectacular but dangerous flames and fountains shot out of the top of the converter. The converter was tilted again and the newly made steel was teemed or poured out. The first converters could make seven tonnes of steel in half an hour. By 1860, John Brown was using this process and other works soon followed. Within 20 years, Sheffield alone was producing 10,000 tons of Bessemer steel every week (this was almost a quarter of the country’s total output). The invention marked the beginning of mass steel production, as huge amounts could be produced in a relatively short time compared to crucible steel production. The steel was most widely used for the railways that were stretching around the world. " ( The Museum's site)

It is quite impressive how from these huge metal machines only 3 of them still stand up in all the world.

The Bessemer Converter

2008-10-19T18:42:00.001+03:00

Today while I was solving some chemistry problems I found one, containing the reactions in a Bessemer Converter. As I hadn't any idea what a Bessemer Converter could be, I went to Linus Pauling's "General Chemistry" and there I found that it is an industrial machine used for purifying molten metals with carbon, silica or manganese impurities.

In an ovoid steel container it is molten an alloy containing a metal and impurities (silica, carbon, manganese). When all the mixture is finally in a liquid state, pure oxygen will be pumped in through a pipe ending in the vessel. Therefore the molten mixture will start gurgling in emissions of CO₂. Simultaneously small solid particles of SiO₂ and MnO could be noticed (only if silicon/manganese are present). At this point of the process the temperature of the mixture is lowered enough for the pure metal to become a thick, hot, glowing paste more consistent than the alloy (alloys always have lower melting points than either of its components). The metal will come down on the bottom of the vessel. After that, the pure metal is piped down further. We can easily observe that the reactions which took place in the Bessemer Converter could be described as following: Fe•C + Fe•Si + Fe•Mn → 3Fe + C + Si + Mn

C + O₂ → CO₂ Si + O₂ → SiO₂ Mn + O₂ → MnO

Image from "Discoveries & Inventions of the Nineteenth Century" by Robert Routledge

The industrial use of the Bessemer Converter is to recycle steel or cast iron by oxidising the impurities in order to produce pure iron. Irons' oxidation doesn't take place, just because the minimum temperature for the reaction to take place isn't reached yet.

As a final remark, I consider this invention very interesting because before 1855, the time this machine was invented, there wasn't known any chemical process of separating carbon from Fe•C alloys.

The major difference between the electronic neutrino and the miuonic one

2008-10-15T18:58:00.000+03:00

A few months ago, I was reading the nuclear physics chapter ("Visiting the 'Atom Smasher'") from George Gamow's book "The New World of Mr Tompkins" (in Romanian) when I found some information on the particles, especially on the neutrino. But because things were treated in a very general way of speaking, and of the fact that I am very excited to read about these kind of things, I looked after a more detailed explanation in some books on the subject such as "In Lumea Atomului" by Natalia Fiuciuc. What I saw there, made me understand, or at least make a wider view of some concepts, such as Particular Leptonic Number and the specific interactions in which muonic the neutrino appears (v_μ) or the ones in which electronic neutrino appears (v_e^-), which is in fact the main difference between them. It has been observed that v_μ comes only with the muon (μ) and v_e^- only with the electron/positron. Furthermore, it has been known for some time that in the pion (π) disintegration there are generated only μ and v_μ. So, in order to sum up the precedent idea we can say that μ and v_μ are implied only in weak interactions whereas e^- and v_e^- just in powerful ones. So from this point of view, scientists could give a classification not only by the power of the interaction but even by a specific leptonic number: miuonic respectively electronic. The three laws of leptonic numbers: 1. The sum of leptonic numbers in a reaction ( L_e^- and L_μ remains the same till the end of the reaction . 2. The electronic leptonic numbers of an electron / neutrino electronic take the value +1 and the poziton/anti-neutrino electronic -1 . 2'. The muonic leptonic numbers of an muon / neutrino muonic take the value +1 and the anti-miuon/anti-neutrino miuonic -1 . 3. The muonic leptonic numbers of the electron / neutrino electronic are 0 and electronic leptonic numbers of miuon/neutrino muonic are also 0 . The law is applied also for their anti-particle.

The Synthesis of Hidrocloric Acid Using Only H2O, Anthracite and Chlorine

2008-10-14T21:25:00.001+03:00

Today, while I was looking through an old chemistry book, I stumbled upon a problem from the USSR National Olympiad which was given about 20 years ago. It had a very practical result and, beyond that it was very straightly formulated. " Knowing that you have only anthracite, H₂O, and Chlorine propose a way of producing HCl in concentrated solution. (Note: you can use only industrial high temperature ovens and adequate laboratory glassware!)" As I was thinking of different ways of solve this problem many ideas have crossed my mind. Firstly I thought it was all about organic chemistry. And may I say none of the rather simple organic compounds satisfied the description of this chemical processes. Finally I gave up and looked at the answer part of the book. What I saw there rather shocked me. Because of the anthracite mentioned in the problem's text we had to imagine that it was a reaction which took place at high temperature. An other clue was the oven of course! Haven't you realised what I'm talking about? The synthesis of the aqueous gas from the reaction C + H₂O = CO + H₂. So the next step was obvious H₂ + Cl₂ = 2HCl .

Hello World!

2008-10-14T21:00:00.002+03:00

Hi I am Andrew from Galati, a rather big town on the bank of the Danube.I am 16, in the ninth grade at the "Vasile Alecsandri" National College. I can say I am passioned by chemistry because it seems very interesting for me to understand the processes that take place in each ad every thing that surrounds us, even beyond the visible line, in the small world of atoms. With this blog I intend to express myself about the things that I consider to be very interesting, not only in pure chemistry but also from the domains of biochemistry and the pfysics of particles. I hope you'll like this!