Horza2002

http://www.cem.msu.edu/~reusch/VirtualText/proteins.htm

This website explains it rather well. If you look on the right hand side, theres a Fischer projection of gylcine...just replace the central hydrigen R group with the relavant thiol to get cystein

It will look exactly the same as all the other amino acids but with the releavent functional group. Presemebly you have the structure of serine...it will be exactly the same but replace the hydroxy with a thiol

Basically, people are just going to have to be careful in how they say things then. I would also like to agree with moontanman in that people favouring relegion are also held to the same standards

Remember that Cahn-Ingold-Prelog rules are just rules. Because cystein has sulphur and selenocystein has selenium the side chains override the priority of the carboxylate group

Lol thanks for the advice....but my spelling was this bad long before I got near solvents!

Not matter what the subject, calling people idiots doesn't get a discuss/arguement anywhere anyway. All it leads to is people making personal attacks on each other and not talking about the topic.

There is definately a feeling that once relgion is mentioned, you should just stop and accept whatever the other beleives; I personally think that is wrong. But as Cap'n Refsmmat points out, this forum is going to be mainly about peoples opinions not facts and so there is no right or wrong anwsers (ignoring subjects with evidence for them)

Its going to be very difficult to argue a point and not get personal where relegion is involved though. So many people really do hold their beliefs to extreme levels and anyone arguing against it will seem to be personally attacking them.

It shouldn't be this way but unfortunately it is. If people have a differernce of opinion in, say, polictics, they are actively encouraged to discuss/argue there side of the coin until they come to a agreement (well supposed to). However, once relegion is mentioned, all of a sudden your not allowed to discuss/argue your side becuse its "disrespectful" to the others beliefs.

Pyridine and most amines smell disgusting so they are definately out...

I quiet like the smell of ether and ethyl acetate....slightly worrying!

Well technically O2 is blue...but you can only really see it in the condensed phase. Other than that, neon will change colour is you pass an electrical current through it (i.e. neon lights)

That does seem very bad to be honest. I live in the student area of Leamington Spa and I've never had a problem. The worst I've had is a group of drunks start making fun of me...only to shut up when my friends the american football team came over to see what was going on!

Arr ok sorry I understand what you mean now. And I agree that yes, some areas of science can be simplified by ignoring sub-atomic particles.

When I last studyed particle physics, quarks are not considered elementary particles because they are not observed on their own. They are always found in pairs or triples....so they aren't fundamental particles. Electrons on the other hand are currently classed as fundamental particles as they are not beleived to be made of anything else and can be observed on their own

Merged post follows:

Timo, chemistry does have a very major use of the structure of nuclie...they're called isotopes!! They are extremely important in determining mechanisms and other processes.

I've never heard of using sulfuric acid as a TLC dip before to be honest.

I agree with your reasoning that the iodine complexes to carbohydrates so it becomes visible. Normally, KMnO4 is a universal TLC dip and that seems to show almost all compounds....onyl ones without oxidisable don't show up

The force Mr Skeptic is describing due to electron density fluctuations is called Van der Waals forces if you want to go read about them.

http://en.wikipedia.org/wiki/Van_der_Waals_force

Well I see your point, if you dilute it enough...but hydrogen peroxide decomposition is catalysed by metals...so depending on what you eat/wear braces...I could envisage it maybe making some problems....maybe I'm just thinking its worse than it is

Try looking up the MSDS data for it and see what it says

To be honest, I'd be more worried about putting hydrogen peroxide in my mouth! It's not exactly the nicest chemical in the world at the best of times.

Typically, the media has little idea what actually goes into making predictions about anything. You can also bet your bottom dollar that if they had not issued a warning and there had been a major wave then the scientists would have been wrong again.

Benzene is an extremely stable molecule because it posses aromatic stabilisation. Sulphuric acid is not strong enough to distrupt this stabilising energy of benzene by protonating it.

Even though there are some virtual model kits, I doubt there will be any free ones. But I myself am a chemist student....and a really 3D model is soooo much mroe useful than a 2D representation. I would highly highly recomend getting a ball and stick kit....it will be invaluable esp when looking at chiral molcules

Hey. Unsaturated fatty acids have carbon-carbon double bonds in them. These are very suseptible to radicals as they can undergo reactions. Try looking up radical chemical reaction.

The questions is:

Predict the products of the electron transfer reactiong giving your reasoning. Sketch the structure of the electron transfer transition state that is consistent with your reaction.

[Co(NH3)5(NCS)]2- + [Cr(OH2)6]2+ ==> ?

Well the thiocyano group is a bridging ligand and so I would expect an inner sphere mechanism with the sulphur displacing a water from the chromium complex.

If I make the assumption that it is a typo and it is actually Co(III) d6, then the Cr(II) d4, would become Co(II) d7 and Cr(III) d3. The Cr(III) would then be low spin and reasonably inert.

Yer after a little bit of thought and discussion I also came to it must be +2 not -2.

It was a question on last years exam paper from our university. The lecture who set it is not here anymore and so we couldn't go ask him.

Hi,

Its revision time again! I came across this metal complex [Co(NH3)5 (NCS)]2-

This implies that the Co is in the -1 oxidation state and therefore a d10 species. My question is this, how can a metal have a negative oxidation state and still form a complex. Surely the negative charge would repel the incoming, potential ligands; especially the anion thiocyante. Also if its a d10 species, it will have no CFSE and therefore be very labile and will exchange with the solvent it is present in...

Horza - yes I know this is the fear. However, we are assuming that the Iranians are actually insane and willing to disappear in a puff of nuclear smoke by Israeli missiles fired from the nuclear Dolphin class submarines and from the rest of the Western world. Or is it more likely that there will be limited warfare in Iran and that we Western forces will have to commit to regime change and sell off the surplus oil and gas reserves in Iran to benefit them in the future? Cynical perhaps...

I totally agree with what your saying, they would have to be mad to attack Israel (with nukes or otherwise). But having openly said they'd would like to destroy them, that maybe a sign that they'd go through with it...