Naked Science Forum
Non Life Sciences => Chemistry => Topic started by: paul.fr on 17/05/2007 11:23:38
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everyone knows that H2O is water, but what substance has the longest chemical symbol? or, what substance do you know whith a rather long chemical symbol.
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I think the formula for aspirin is quite long. I know that the formula for Perrier water is H2OkayYah [:D]
But for really long formulae, how about beer? That's got loads of stuff in it.
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everyone knows that H2O is water, but what substance has the longest chemical symbol? or, what substance do you know whith a rather long chemical symbol.
Diamond.
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Try the chemical formula for DNA.
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Try the chemical formula for DNA.
Yes, but a diamond's formula is longer (it's a polimer, the molecule is as long as the entire crystal. Of course I choose the simpler it came to mind).
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Try the chemical formula for DNA.
Yes, but a diamond's formula is longer (it's a polimer, the molecule is as long as the entire crystal. Of course I choose the simpler it came to mind).
Polymers did occur to me too (I thought first of something like polyethylene, or polypropylene), but the point about polymers is that they are repeated chains of monomers, and so they could be written out in simplified form.
Diamond (as the simplest example) may be a very big molecule, but a diamond crystal containing 1 million atoms could simply be written out as C1000000, while a 1 million chain polyethylene molecule could be written as C1000000H2000002. The non-repeating nature of DNA meant there are no short cuts to writing out the entire formula.
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I suppose it depends on what you mean by molecular formula. Generally, there are many ways of representing compounds. For instance, both ethyl alcohol and dimethyl ether have the same molecular formula of C2H6O. Unfortunately, the molecular formula usually doesn't give enough information to identify the compound in question. For that, we often turn to the condensed formula (or sometimes graphical representations), which can be very long indeed, even disregarding polymers. The aforementioned ethyl alcohol and dimethyl ether have condensed formulas of CH3CH2OH and CH3OCH3, respectively.
Going to something as relatively easy as magnesium stearate (found in soaps among other things) we have a molecular formula of C36H70O4Mg, and a condensed formula of CH3CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CO2MgO2CCH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH3
Of course, we generally don't want to write out those long formulas, so we find ways of shortening them, as follows:
(CH3(CH2)16CO2)2Mg
(there are two groups on the Mg, each containing an 18 C chain of atoms)
Dick
P.S., there is a shortcut for DNA/RNA. Each monomer (repeating unit) is only different in the identity of the base that is present. There are only 4-5 different bases that are found in DNA/RNA - each is represented by a letter (e.g., G for the guanine base). The strand of DNA is then represented by which base is present in each repeating unit, such as GTCGAGCACGCT.
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P.S., there is a shortcut for DNA/RNA. Each monomer (repeating unit) is only different in the identity of the base that is present. There are only 4-5 different bases that are found in DNA/RNA - each is represented by a letter (e.g., G for the guanine base). The strand of DNA is then represented by which base is present in each repeating unit, such as GTCGAGCACGCT.
I am not sure that the base sequence would actually be classed as a chemical formula as such, but even if that was accepted, mapping all the bases in the human genome (even in a single chromosome, particularly for some of the larger chromosomes) is still a massive formula.
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Strictly speaking the elemnts have symbols and compounds have formulae. Up until recently the chemical symbols were 1 ro 2 letters long. IUPAC decided to do away with the arguments over the names of newly created heavy elements by naming them after the (greek prefixes of) the atomic number so, for example element number 121 in the periodic table would be called unbinubium (I think) and have the symbol Ubu which strikes me as even more silly than having an argument over the name.
Heres some explanation.
http://www.chem.qmul.ac.uk/iupac/AtWt/element.html
Since the human genome is carried on a number of chromosomes which are separate, each of them is a single molecule. This means the chemical formulae would be a bit shorter. I don't know what the biggest chromosome is.
Even with the enormous complexity of a chromosome it only contains a handful of elements; it could be written as HuCvOwNxPy where u,v,w,x, and y are the number of atoms of each element in the molecule. That's not a very long formula. Other compounds win if you count the number of different elements present.
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Strictly speaking the elemnts have symbols and compounds have formulae. Up until recently the chemical symbols were 1 ro 2 letters long. IUPAC decided to do away with the arguments over the names of newly created heavy elements by naming them after the (greek prefixes of) the atomic number so, for example element number 121 in the periodic table would be called unbinubium (I think) and have the symbol Ubu which strikes me as even more silly than having an argument over the name.
Heres some explanation.
http://www.chem.qmul.ac.uk/iupac/AtWt/element.html
Actually, these names are temporary placeholders until official names can be decided upon after the elements are actually synthesized and after much deliberation (and controversy, and maybe some name-calling). This allows people to talk about them before they have official names. For instance, seaborgium (#106) used to be called unnilhexium until an official name was decided upon (rutherfordium, later changed to seaborgium).
Dick
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Nobody can say a certain molecule.It depends what you actually mean.Because polymers have very long chains thats why called as poli-