@LegionMammal978 Often it is presented just as (CH2)x. To a large extent it's purely a stylistic preference, as the two expressions are chemically identical. (C2H4)x does emphasize more directly the nature of the actual monomer, though.
@orthocresol Yeah, at the church we were going to for a while, the waiting list for clarinet slots in the orchestra was at least three people deep, whereas they were desperate to find an oboist.
I understand that the monomer that polymerises to give polyethylene is an ethylene, but after polymerisation, the smallest repeating monomer in polyethylene seems to be a methyl and not an ethyl. So why don’t we call it polymethylene instead?
@Loong Based on your comment by yesterdat on my answer about a bromobutene here
The suggested name “(E)-bromo-2-butene” is ambiguous and not in accordance with IUPAC nomenclature. The systematic name is (2E)-2-bromobut-2-ene. — Loong ♦yesterday
and the distance to the own answer given multiple months ago, there are two aspects.
For one, I agree with your comment to use the labeling more explicitly, especially about the position of the bromine.
On the other hand, naming the sole double bond present in the molecule not only (E), but (2E), suggests that I missed something.
I have seen names with multiple (conjugated or isolated) double bonds where their position and configuration was labeled simultaneously and explicitly as in your comment.
Is following the more explicit way you used a) a recent recommendation by IUPAC (say, after 2010), or b) did it become a rule? (I would be fine with the [pythonic] approach "explicit is better than implicit", i.e. likely to use your pattern regardless of the number of double bonds to describe -- even if there is only one.)
Sorry, drawing the molecule with paper and pen I recognize that I erred in my argumentation.
You are right in using the explicit notation because the description of the double bond needs to account both configuration and position within the butene chain, too.
No action by your party is needed. Thank you for pointing out the issue.
I understand that the monomer that polymerises to give polyethylene is an ethylene, but after polymerisation, the smallest repeating monomer in polyethylene seems to be a methyl and not an ethyl. So why don’t we call it polymethylene instead?
The Periodic Table
The Periodic Table