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Theophrastus

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  1. Ah, I've been doing some research and I don't have the whole answer, but I may have part of it. The Mannich reaction is one that leads to a product of an amino- carbonyl compound, which I think, can then be used as a means for the genesis of amino acids, by using a hydroxyl, as the R3 group. Here's a lovely wikipedia link which explains the reaction... http://en.wikipedia.org/wiki/Mannich_reaction To do so, in a simplified form, I could use ammonia, formaldehyde and acetic acid, which would result in an amino acid, similar to glycine, only with two CH2's between the amine and carboxyl group. I would then, by means of knowing the isoelectric point, extract the amino acids from possible impurities, (which I admit shall be numerous), however I'm not quite sure about several things. Firstly, will the use of an carboxylic acid group, affect tautomerization? Secondly, is this method viable, and what should one consider in terms of practical application of this? Ah practicality, as wonderful as it is, it is an annoying consideration at times...
  2. Sounds pretty interesting; I'll give it a go. :)

  3. Pretty ironic, because, even before I had read your post, I had already added some pure Fe2O3, and yet it seemed, it did absolutely nothing for the solution, as it remained just as it had before in colouration and acidity, and I simply filtered it off, and left it acidic, as you stated. (personally taking note that if I use it in an applicable chemical reaction, I'll be adding excess of the other reagent, in al likelihood). As for making FeCl3, in contrast to my current FeCl2, I'l use up about half of the mixture, for that, as I made quite literally excessive amounts of FeCl2, and it wouldn't be bad to have both. I'll be getting some PVC pipe to channel the chlorine gas with. I'll post the results, when all has been completed. Thanks for all the help UC!
  4. Class of carbon compounds? No, the buckminsterfullerene, is a carbon allotrope, consisting of precisely 60 carbon atoms, in a lovely geometric structure, in likeness to a soccer ball. Allotropes are simply different 3- dimensional structures and configurations for a pure element, that result in often vastly different properties, for the substances. and as always, more from our dearest search engine, wikipedia... http://en.wikipedia.org/wiki/Fullerene http://en.wikipedia.org/wiki/Allotropy
  5. My new plan (following suggestion): First, as before, I'll add Fe2O3, in order to use up the excess hydrochloric acid, and forming an arbitrary mixture of iron (II) and (III) chloride. I then have two paths, one: I could bubble in chlorine gas, in order to achieve a purely iron (III) chloride solution, and then boil it off to a attain a hydrous crystalline product. My second option would be to then use potassium hexacyanoferrate to precipitate the iron (III) chloride, forming a dark blue complex. And the filter off the iron (II) chloride. (I realised that I was confusing iron 2+ and copper 2+. For the fomer, I suppose one would use something like potassium triflouride hexacyanide (forgive me if I'm mistaken)) Anyhow, My plan is to go with option 1 as of now, given a low stock of potassium hexacyanoferrate, though I'll have to purchase some PVC pipe first. Thanks for all the help UC!
  6. Thanks for the response UC. Ironically, I had added excess (far too much given the solution's pH value of around 0.6) HCl, and tonight was thinking of a means to rid myself of it. I was thinking of adding some Fe2O3, to use up the acid, and then adding ammonia, to precipitate a iron (II) ammonia complex, at which point I can filter off the FeCl3, separating it from the complex, and then with mild heating decompose the complex, to attain ammonia gas and iron (II) chloride. This I would then, as you told me, add slight excess HCl, to decrease, oxidation to iron (III) chloride, leaving it in stored solution form. By the way, is there any means to speed up the oxidation process of FeCl2, sufficiently so as to ignore it, and bypass the filteration? As for the last note- yeah; there are a lot of easier ways to make FeCl2, and I'm not sure, but I would guess the resultant iron (II) chloride to be hydrous, as I believe that the dehydration process involves use of HCl gas- enoough said.
  7. Really? Meh, what the hell- I never was quite good with latex, or dates and times. I thought it may have been new as the layout seemed different, if i vaguely recall. Alas!
  8. While you may look at the thread, and notice its age, just today, I was digging through my chemical "storage room," to find the solution, I had from before, left for months untouched. With much precipitate encrusted on the bottom, I decided to finally clean this ancient mess up, and poured in a generous amount of hydrochloric acid. The solution slowly grew less and less turbid, until it turned a lovely golden colour, almost like honey, and suddenly I realised- iron chloride! The precipitate that had looked black was actually brownish iron hydroxide, while the orangish precipitate was iron oxide! Looking back, I realise that I was using a set of electrodes I had bought which were copper- plated iron, which needless to say would have yielded little copper salt, but substantially more iron. Needless, to say, this unholy mess settled out, my beaker's clean, and I'm hoping to boil down the solution, to reattain some iron chloride crystals, which I'll store for later use.
  9. I was thinking of making some basic amino acids recently, to try some basic dry- heat, protein synthesis. I've been playing around with some basic chemicals I have on hand, but I can't really find a way, to keep the amine and the carboxyl group, from reacting with one another. Any thoughts or ideas? At this point, I'm rather clueless. As always, help is most appreciated.
  10. I know that potassium iodide is easy to buy on the internet, or from a chemistry supply store, but I don't really have the time currently to wait several weeks for it to come in. Boiling off the water and alcohol, I doubt is really safe, as the flash point of ethyl alcohol is 25 degrees celsius, so it is far more likely that the alcohol will burn, and in doing so, you may wind up with some nasty halogenated organic compounds. Basic probabilities taken into account, I'ld much rather bubble in chlorine.
  11. In regards to the benzene, I'm quite sure the solubility is sufficient, as my friend used it in an experiment to test for the presence of iodine ions in a solution, and he waas the one who gave me the idea, so I suppose its functional but not original. I know many chlorinated organics are either known, or suspected carcinogens, but given the fickle amount of iodine within the solution, roughly 7%, I won't need very much chlorine, in the first place, and I'll be sure to keep the reaction contained. In regards to the amounts of ethyl chloride, that will be generated, it shouldn't be of too much concern, as generally amounts around 1-3% should be fine. It's only when things grow more substantial than that, when things become a problem. Still, liking the iodide idea better, it's only natural that I ask- is there any relatively simple means for obtaining potassium iodide, from iodine tincture?
  12. I agree with Bascule on the general idea, and support it full- heartedly. This is definitely something that is required for this forum, as I find, all too often, geology threads, instead left to sit in the Other Sciences section; we might as well find a proper place for it. I agree with baby astronaut on the modification of Ecology and the Environment, to Ecology, which I suppose take to concern itself moreso with biodiversity, and the like. I don't like the elimination of amateur science, as we need a place for applied concepts, as well as simply theoretical ones. It may be asking too much, but is there any means of reorganizing posts, so that the relevant posts in ecology and the environment, are shuffled to their respective category? As for the sub- categories, I like what Bascule said- oceanography, atmospheric sciences/ climatology, geology, and (a little unsure on this one) geophysics. Any thoughts? (given the nature of the question, this is directed particularly to the mods, but if you wish to take part; By all means!)
  13. Well, the one thing about chinese (and by the way there are several dialects which could be denoted as "chinese;" ie. mandarin, cantonese, etc.), is while it is the most widely spoken language, it's very limited geographically. It also happens to be pretty damned hard to learn, for one whose native tongue is Germanic, due to pronunciation. I'ld say to learn Russian, but that's even more limited, however one is of course by nature biased towards their native tongue.
  14. I'ld agree with insane alien, in that if you want to enter a medical profession, latin (or greek!) will be a substantial asset, what with numerous anatomical terms, being derived from latin and greek. If you're keen on zoology, or botany latin can also make it easier to learn the latin names for various flora and fauna, since the names have more meaning, once you are capable of comprehending them. Otherwise, its simply a name that you memorize, and this makes it a lot more difficult. However, outside of these two areas, I find that latin doesn't really do very much in the sciences. Physics is pretty much devoid of it. While in chemistry, you do find compounds that have latin or greek origins, it's very systemic in nomenclature, and as such, latin won't be much of an asset, just a bit of an interesting oddity when you realise where certain things derive from, but other than that, it does little, from a practical perspective. Spanish and German, have little to do with the sciences, directly, however its often useful to learn a second language. (In saying this of course, I'm sadly being a hippocrite, as I plan to give up french, as soon as its no longer mandatory. To put it lightly, my teachers are horrible (remember that this is putting it lightly), and I have no interest in the subject.) But like a lot of things in life, it's all about personal interest. It depends upon what you find interesting in subject, what you dislike, and what you value, and (I would be a naive moralist, if I did not say otherwise) what is required of one. Anyhow, all things set aside, best of luck in your choice!
  15. I'm actually thinking of trying an experiment, quite similar to this. I plan to generate chlorine gas by mixing hydrogen peroxide, and hydrochloric acid, (in a consequently sealed glass flask) proceding to funnel the resulting chlorine gas, by means of clear PVC pipe, into the iodine tincture (which I would place in a glass erlenmeyer flask), where the iodine would then precipitate. Even though I like albgk's idea a bit better, I simply want to try this out to see how it works. To get a cleaner product, I plan to use C6H6 as a solvent, into which the iodine should dissolve, but the potassium iodide, potassium chloride, and ethyl alcohol would not. If all goes well the C6H6 layer, should quickly turn purple. Any thoughts upon the layout?
  16. In regards to the structure and binding of haemoglobin, and its allosteric properties, should one know the graphic method of ataining the Hill coefficient? Should one also know how to analyse a double reciprocal plot of enzyme catalysis? And is there anything on the test in regards to the structure and function of extracellular proteins? ps: Don't worry, I'm not taking the test myself...yet. I'm just interested in terms of what one is allowed to skim over, in contrast to that which is necessary. (Despite their necessity, pKa values by nature, I find to be a nuisance.)
  17. Testing Testing! [ce] CuCl2 + Na2CO3 -> CuCO3 + 2NaCl [/ce] [ce] CH3CH2OH ->[{alcohol dehydrogenase}] CH3CHO + H2 [/ce] [ce] Mg + 2H2O -> Mg(OH)2 + H2 [/ce] [ce] Cu + Zn^2+ -> Cu^2+ + Zn [/ce] [ce] FeS + 2HCl -> FeCl2 + H2S [/ce] [ce] H2O2 + SO2 -> H2SO4 [/ce] [ce] Acetate + CoA- SH + ATP <=>[{acetyl-CoA synthetase}] Acetyl-S-CoA + AMP + PPi [/ce] [ce] HCl + H2O <=> H3O+ + Cl- [/ce] [ce] -OOCCH2CH2COO- ->[{succinate dehydrogenase}] -OOCCH=CHCOO- + H2 [/ce] [ce] {{x}}_ CuSO4 + 4NH3 -> Cu_{{x}}(NH3)4(SO4)_{{x}} [/ce] [ce] RNH2 + CO2 <=> RNHCOOH <=> RNHCOO- + H+ [/ce] Absolutely brilliant; and a fair bit easier to play with than its predecessor, which in itself is a much needed improvement; awesome job Dave! I do believe that reputation points are in order...
  18. Wait, I'm actually rather confused. Are you refering to an isolated experiment with heparan, or is it a cellular process you're working with? A little more articulation would be most appreciated.
  19. Oh damn- MeMgBr is a strong base? Looking back, I've realised I forgot to factor in electronegativity. That taken into account, the methyl carbon, would by nature have a partial negative charge, and thus would make an excellent proton acceptor. Is there anything else, I missed in my analysis?
  20. Of this, I'm not quite sure. I'll give it a shot, but don't take my word for it. Anyhow, I know imadazole is weakly acidic, however, despite being amphoteric, it does come up far more prominently as a base. As an acid, it is simply rather weak. The second compound, methylmagnesium bromine, seems to be only weakly basic, (if the information you've given is true) due to the possibilities of the methyl group, being protonated under acidic conditions. Anyhow, I really see two angles from which the imadazole can attack the MMB (not a common acronym, but I'll use it to cut down on length)- from the bromine side, however the result will be that the imadazole ring ion, will have taken bromine's place, and formed hydrobromic acid. Not only due to the magnesium's affinity for the bromine ion, in contrast to the imadazole ion, and the low strength of imadazole as an acid is this reaction unlikely, but as the end product shall produce hydrobromic acid. A much stronger acid to be sure, the reaction will quickly reverse itself, thus it shall be of little consequence. Far more likely, will be the fact that it will instead protonate the methyl group, (perhaps resulting in intramolecular forces between the two molecules, as in contrast, imadazole's conjugate basic ion, is quite strong) however, while this may occur, it shall do so too infrequently to be of much consequence. No offense, but I don't believe I see the possibility of a serious reaction here. Sorry to have burst that bubble.
  21. I shall address your ideas in turn. To test for chloride, you must find a way to precipitate it. Knowing that AgCl is insoluble means that all one needs to do is add a silver salt or compound, to achieve the desired effect. In this case, silver nitrate would work finely. Implying the solution is sodium chloride, you would be left with dissolved sodium nitrate, and a white tell- tale silver chloride precipitate. To test for sulfate, in a solution, you can perform a similar procedure with a barium salt, and if the sulfate ion is present, you will be left with a white barium sulfate precipitate. The hydrogen carbonate ion, you can test in a similar fashion to the carbonate; simply by adding dilute 0.1 M hydrochloric acid (or really any other sufficiently strong acid for that matter, it's just, the latter is common procedure in the lab) If this results in the release of a nonflammable gas (carbon dioxide), then you know that there are carbonate, or hydrogen carbonate, present in the solution. Its key that the gas is nonflammable, as hydrogen is commonly released, if there are metallic cations floating about. Other flammable organic compounds can also be produced- which is of course- undesirable. As for phosphate ions, that I'm actually unsure about, as I'm not so familiar with phophate salts, however, you can play off of insoluble compounds in a similar fashion, and as long as it holds no common with another salt bearing the same cation- you're clear. (Or you can simply perform further testing upon attaining the insoluble residue, however, unless it isn't possible, option 1 would be your best bet for simplicity's sake. Anyway, hope this helps answer your question. If you have any others, feel free to ask, ,Theo
  22. Yeah, I'm sorry I didn't articulate, I was in fact particularly refering to bulging veins in the distal ends of the extremities. And I definitely agree with what Mokele said in regards to blood volume. I also realised that in terms of what I seemed to vaguely remember about heat, was that bloood vessels closer to the skin, dilate when it is hot, so as to regulate the body temperature, in response to environmental conditions. I was thinking on a similar basis that my trend is simply because of paler skin, of Europeans in the region, which contains less defensive (against the sun) melanin, thus meaning more absorbsion of heat through radiation, or is this difference, really significant enough to induce the effects described, or at least play a fairly significant role? I'm also interested though, in whether blood pressure may have anything to do with it, as one of my friends IIRC, made a comment in regards to it, when I told him of this- Any thoughts?
  23. Thanks for all the links, and the clear, and wonderfully elaborate explanations; I'm really at a loss for words (I have laringitis ) However, looking back, and attaining a bit of work on chirality, I realised another question, that I should have asked: Let's say we have the molecule 2, 4 chlorohexane, instead of simply 2 chlorobutane. Here you would have 2 stereocenters, in place of one. In such an event, in listing the R and S, I would assume that, the listings would be done numerically; first the second carbon, then the fourth. Is this assumption correct?
  24. In regards to water, I was actually at a time, teasing my not- so- chemistry savvy friend that in one of my experiments, there was a leak of "deadly" "dihydrogen monoxide" () gas. To my greatest bemusement, four periods later, he was able to convince numerous students and unsuspecting educators, (using various made up stories and fake references) to sign a petition to ban the dangerous chemical, from the public sphere. Damn!- I laughed like hell after that one! (several periods later, so as not to seem the fool, lest research was done, on people's part, he admitted his own trickery: though the consecutive responses to this gesture were... dare I say it... mixed. )
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