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Original post by reneetaylor
So what was the reagent used?

It was NaBH4 I think, the carboxylic acid bit wasn't reduced in the reaction, just the ketone part.
Reply 3181
how did people get 63.2? pretty sure most people i spoke to got 63.5 % :s-smilie:
Reply 3182
Original post by keepontrying
yes and splitting patterns and analysed the carbon nmr, I didn't actually say heptet I multiplet for that one but did name others , both are accepted on previous m.s though



Please tell me I spelt heptet right! lol!

then you are fixed! :smile:


what was the answer for the monomer third monomer last question

I got

if i remember the benzene ring with C-C and i put the double bond oxygen too?
Original post by Gulzar
I got something like 63.5 percent for the percentage yield.


Indeed, I remember get a figure around this ball park. Can anyone remember the masses? Or even better, get the paper up?
Reply 3184
Original post by topdoc.
how did people get 63.2? pretty sure most people i spoke to got 63.5 % :s-smilie:


well it was 63.15 but correct to 3 sig fig comes to 63.2
Original post by otrivine
read the book, they put the benzene what ever reacting with the HNO2+HCL

http://www.ocr.org.uk/Images/63346-mark-scheme-january.pdf

evidence for you :tongue:

yeah your right they do accept it sorry my bad, i just thought ocr being ocr may be really picky
Any unofficial mark scheme going on guys?
Reply 3187
Original post by topdoc.
how did people get 63.2? pretty sure most people i spoke to got 63.5 % :s-smilie:


I got 63.5 :wink:
Reply 3188
I got the right structure but in the stress of the exam I wrote it down wrong in the box:frown: put the benzene then ester but stupidly put a H attached to the C(double bond)O ! How annoying! How many marks do you think I will lose? It's usually 2 or 3 for the structure isn't it :frown:


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Reply 3189
Original post by Patel3000
yeah your right they do accept it sorry my bad, i just thought ocr being ocr may be really picky


its fine :smile:

did you get 63.2% ?

and was your structure with the benzene first and then the ester and the CH(CH3)2
Original post by topdoc.
how did people get 63.2? pretty sure most people i spoke to got 63.5 % :s-smilie:


I did too, our issue was miscalculating the MR of compound G... I ****ing hate doing those questions, so easy to mess up.
Original post by JeevenSD
It was NaBH4 I think, the carboxylic acid bit wasn't reduced in the reaction, just the ketone part.


Nice :smile:
Reply 3192
Original post by otrivine
if I remember it came to 63.15 somethign so to 3 sig fig i get 63.2 % ?


Answer was 63.5/6 (depending on roundings)
The Mz value for the compound was 174 because 160 + 16 (for extra oxygen) - 2 (for 2 lost hydrogens)
Original post by otrivine
Please tell me I spelt heptet right! lol!

then you are fixed! :smile:


what was the answer for the monomer third monomer last question

I got

if i remember the benzene ring with C-C and i put the double bond oxygen too?


not to sure which question you are reffering to perhaps if you described a bit more please
Reply 3194
Original post by OwenL
Answer was 63.5/6 (depending on roundings)
The Mz value for the compound was 174 because 160 + 16 (for extra oxygen) - 2 (for 2 lost hydrogens)


I got 174

maybe I put 63.5 , cant remember but I did get 174

and got two moles and divided them
Reply 3195
I think I dropped 4 marks in the worst case scenario. Need 85/90.


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Reply 3196
Original post by otrivine
I got 174


I did too.

I dropped naming the amino phenol with Bromines on it and the CuI part. Everything else I got right. :biggrin:


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Original post by otrivine
its fine :smile:

did you get 63.2% ?

and was your structure with the benzene first and then the ester and the CH(CH3)2


i think i got 63.5 but i'm not sure

yeah same for the last one did you the benzne-OOCCH(CH2)3
Reply 3198
Original post by OwenL
Answer was 63.5/6 (depending on roundings)
The Mz value for the compound was 174 because 160 + 16 (for extra oxygen) - 2 (for 2 lost hydrogens)


same! i got 63.5%, i think people didnt realise there was a CH3 on the triangle and mis-calculated. i got 174 for the Mr of G :-)
Reply 3199
Original post by GinaS
I got the right structure but in the stress of the exam I wrote it down wrong in the box:frown: put the benzene then ester but stupidly put a H attached to the C(double bond)O ! How annoying! How many marks do you think I will lose? It's usually 2 or 3 for the structure isn't it :frown:


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I'm afraid so :frown:
I hate to be the bearer of bad news but half of the marks usually come from the structure alone but as long as u showed your working out they will give u the other marks :wink:

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