Okay scratch that then. Groups/atoms in a molecule are said to be "chemically equivalent" or "in the same environment" if the structure of the molecule is such that they are joined to the same groups/atoms.
e.g.
The molecule is symmetric about the 3rd carbon, so the protons on the 1st & 5th and 2nd & 4th are equivalent.
However the molecule need not be symmetric:
This molecule has almost no symmetry but there are equivalent proton environments on the phenyl substituent (the 6-memebered ring with alternating double bonds), as the 2/6 and 3/5 protons are equivalent (counting clockwise around the ring, starting where the phenyl is joined to the other part of the molecule).
There doesn't necessarily need to be symmetry: see above.
Awesome this really helps, the environment thing has come up twice in vocabulary and it will really help with the questions.
I did this last year, I remember walking out very perplexed and thankful for how much easier my AS chemistry exams were. Ended up with a Silver which I was fairly happy with given that no work was put into it.
For the 2011 paper. why do the deuteriums have to be on the carbon not involved in the double bond rather than the double bonding carbon on the end of the propene, given that they're in the same environment?
Hi all, I'm new to this thread and the Cambridge Chemistry Challenge, I've completed the first two June 2015 online challenge and i'm stuck on the Sliver Level Question which is titled 'Whose Nail?'. I'm a little bit confused as the image background shows the molecular model of C20H14N4 which is Porphin and the answer is not Porphin! So please help me with this question
Hi all, I'm new to this thread and the Cambridge Chemistry Challenge, I've completed the first two June 2015 online challenge and i'm stuck on the Sliver Level Question which is titled 'Whose Nail?'. I'm a little bit confused as the image background shows the molecular model of C20H14N4 which is Porphin and the answer is not Porphin! So please help me with this question
Hello there, if anyone is still here doing the chemistry challenge puzzles, would someone be kind to share with me the hints to the roentgenium challenge in February 2015? I have no idea to what ion they expect us to use. I have done every single other chemistry challenges and this is my last one. Huge thanks.
Hello there, if anyone is still here doing the chemistry challenge puzzles, would someone be kind to share with me the hints to the roentgenium challenge in February 2015? I have no idea to what ion they expect us to use. I have done every single other chemistry challenges and this is my last one. Huge thanks.
I got the answer (around 10^-6) using the two equations Ek = 1/2mv^2 and s = vt, equating them using v. You may also need to know from a level physics that V = WD / Q (voltage is work done per unit charge). To help you out the ion is the phenyl cation.
I got the answer (around 10^-6) using the two equations Ek = 1/2mv^2 and s = vt, equating them using v. You may also need to know from a level physics that V = WD / Q (voltage is work done per unit charge). To help you out the ion is the phenyl cation.
OMG THANK YOU SO MUCH!! Also may I please ask you for the silver level question for January 2015? I just need the question, not the answer. For some reason I can’t view the real question due to some glitch happening, instead I saw a wrong picture for another question on fireworks, which is wrong. thanks so much for helping me complete the challenges, this silver question is the real last one. 😊 (I know I said the Time of flight question is the last one in my post before but this is my real last one lol)
OMG THANK YOU SO MUCH!! Also may I please ask you for the silver level question for January 2015? I just need the question, not the answer. For some reason I can’t view the real question due to some glitch happening, instead I saw a wrong picture for another question on fireworks, which is wrong. thanks so much for helping me complete the challenges, this silver question is the real last one. 😊 (I know I said the Time of flight question is the last one in my post before but this is my real last one lol)