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OCR A2 CHEMISTRY F324 and F325- 14th and 22nd June 2016- OFFICIAL THREAD

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I am quite good and that, on the other hand, I tend to stumble at word questions at topics like triglyceride, degradable stuff, chromatography. There are quite a lot of them this time, and no nmr for me to back up my marks i am really frightened now :frown:

you literally just mentioned all the other topics ? but dw im sure u will be fine

Reply 1861

dotbot

Original post by RBoss

% yield = mol of A/mol of phenylamine *100

so mol of A = %yield /100 * mol of phenylamine

mol of phenylamine = 3.00/93 = 0.03225...

so moles of A = 0.03225* 0.61 = 0.019677...

So mass = mol*mr = 0.019677...*135 = 2.65645... = 2.66 to 3 sf

i did the exact same as this too.

Reply 1862

Magicalgeofray

https://docs.google.com/document/d/1sJ1zRjH6XZ0MwCAI7JIVbP_WobX4JL2jcdvYh3NHFKs/edit unoffical mark scheme link

Reply 1863

FluffyCommie

Original post by maisym00

When naming the type of condensation polymer would polyamide be sufficient or did you need to put nylon

It asked for the TYPE of condensation polymer, so "Polyamide" would be sufficient :smile:

Reply 1864

mp_x

For the poly(lactic acid) one i put it is biodegradable and it breaks down into co2 and h20 as that is the definition of biodegradable in the book, is this wrong?

Reply 1865

MfMcD

Enthanoic acid? I'm not sure though

Original post by sydneyl3igh

What was the other organic product in the ethanoic anhydride question?

Reply 1866

Lularose83

I think F325 is going to hit us hard. No way would they make f324 that easy otherwise... It's just the calm before the storm!

Reply 1867

_NMcC_

I got 2.66g for percentage yield. The question was like what mass of compound D can be produced from 3.00g of the other compound. They gave you 61% yield. I think KB_97 (above) is right for the final question as there was a peak in the C13 nmr spec that was too far to the left to be a carboxylic acid. No result with Tollens, therefore Ketone for G. I think they tried to confuse us by saying 'reflux' - so you automatically think carboxylic acid--, 4 carbon environments meant that there were two CH3 groups in the same environment. Quite a sneaky question but nowhere near as hard as last year's analysis Q.

Pray that the grade boundaries aren't going to be ridiculously high.

Reply 1868

NervousBoy

Original post by ali_t9001

was the multiplet a sextet?

It was:

Doublet

Sextet/Multiplet (Either)

Doublet

CH3CH(NH2)CH2OH was the compound with D2O added

Reply 1869

RealistZ

Original post by ali_t9001

Ethanoic acid

It's propanoic acid CH3CH2COOH Mr=74

Reply 1870

May0145

For Compound C: was it OH on the phenol or O- reacting with the azo group?

Reply 1871

lai812matthew

I don't think hextet is right as it is an assymetrical molecule

Reply 1872

GawdHeresEmmie

Original post by KB_97

I wrote about the cooh and oh groups on lactic acid hydrogen bonding with water in the body?? Didn't wanna get to biological bc its a chemistry exam.

I said about that too!

Original post by maisym00

I did this on literally in the last 30 seconds so might not remember correctly, but I think I got a doublet at 1-2 due to CH3, a hextet at 2-3 due to HC-N? (This is the one I wasn't sure on lol) and a doublet at 3-4 due to HC-O

Pretty sure I got the same just I put 'multiplet' instead x

Reply 1873

bakedbeans247

Original post by lai812matthew

Got any f325 preditcions? I think someone replied to you saying you predicted well for f324? if so, f325 please! Thanks! :tongue:

Reply 1874

lai812matthew

I write helmet on the Kevlar question because I don't know how to called the clothing

Reply 1875

uk_shahj

Original post by Iamjos

I got something similar like 7.14g! How did you guys work it out?

I got that, it's wrong though. We used the ratio of 100/61 and multiplied the mols of phenylamine by that. We should have multiplied by 61/100. Hopefully we get 1 or 2 marks? I think it was a 3 mark question

Reply 1876

jerseyalevel

Is it wrong to describe the splitting as a hextet ? (6)

Posted from TSR Mobile

Reply 1877

anndz3007

Original post by Irmakozturk

aaaah i wasn't sure at all but it put

OHCH2CH2CH(NH2)CH2CH2CH2OH

i dont remember exactly where the oxygen on the rhs was tho but all my numbers matched so idk if its right or coincidence

OHCH2CH2CH2(NH)CH2CH2CH2OH i think, cus if you do NH2, N would be positive no ?, im freaking out cus i did it with NH but still put + on the N, i remembered me erased it, but i got some kind of deja vu that i put + sign back on again

Reply 1878

GawdHeresEmmie

Original post by KB_97

I got this for the last question. Compound J I think. Anybody else get this?

meeee 🙋🙋

Reply 1879

KB_97

The unofficial make scheme Google document is a hot mess. I'm gonna put what I got the last structures on here. If you got the same as me thumbs up if not say what you got and we'll see who agrees/disagrees