Please could someone explain the mark scheme, since I did nucleophillic substitution of a haloalkane to a alcohol first
Would I still be credited marks for this?
I attached my answer and the mark scheme.

(edited 1 year ago)

0BE9AF6B-457E-4CB1-98EA-53D3CE6FD097.jpg367.3KB

46323F4C-9C58-4A63-96DC-59B0B67E3192.jpg299.1KB

Reply 24

simxne_

13

Original post by Astudy

Please could someone explain the mark scheme, since I did nucleophillic substitution of a haloalkane to a alcohol first
Would I still be credited marks for this?
I attached my answer and the mark scheme.

I almost did that when I was doing that question! I'm not sure if that works because in compound A, the carbon chain has been extended and reflux of an alcohol will only replace the -OH with -OOH of the carboxyl group, so to extend the carbon chain, you need to add a nitrile group somehow.

is that what you meant? or were you just asking if you would still get marks for the first part?

(edited 1 year ago)

Reply 25

aliaa03

21

Original post by Astudy

Please could someone explain the mark scheme, since I did nucleophillic substitution of a haloalkane to a alcohol first
Would I still be credited marks for this?
I attached my answer and the mark scheme.

i made the same mistake in my mock and got 0/6, you have to notice the extra C which means you need a reaction to extend the C chain first

Reply 26

Astudy

10

Original post by simxne_

I almost did that when I was doing that question! I'm not sure if that works because in compound A, the carbon chain has been extended and reflux of an alcohol will only replace the -OH with -OOH of the carboxyl group, so to extend the carbon chain, you need to add a nitrile group somehow.

is that what you meant? or were you just asking if you would still get marks for the first part?

yes that's what I meant, thank you!

Reply 27

Astudy

10

thank you, I didn't even notice there was an extra C!

Original post by aliaa03

i made the same mistake in my mock and got 0/6, you have to notice the extra C which means you need a reaction to extend the C chain first

(edited 1 year ago)

Reply 28

dawud.48

6

Original post by othello03

neither but I think I need like at least 70 on this paper to get the marks up 😔😭

make that 80 lol, I counted wrong 💀

How are you gonna prepare for that paper other than memorising synthetic routes. I'm in a similar situation as you cos I flopped paper 1 💀

Reply 29

othello03

10

Original post by dawud.48

How are you gonna prepare for that paper other than memorising synthetic routes. I'm in a similar situation as you cos I flopped paper 1 💀

I literally don't know, the plan is to get home from biology tomorrow at about 12:30, nap until 1:30, eat/chill until 2, and then devote the entire rest of my weekend to chemistry.

to be fair most of this is exam is synthetic routes/mechanisms and stuff. I might try and focus not the recall little content tomorrow, then spend Saturday and Sunday doing every PMT question there is

Reply 30

Iceyballz

8

Original post by othello03

I literally don't know, the plan is to get home from biology tomorrow at about 12:30, nap until 1:30, eat/chill until 2, and then devote the entire rest of my weekend to chemistry.

to be fair most of this is exam is synthetic routes/mechanisms and stuff. I might try and focus not the recall little content tomorrow, then spend Saturday and Sunday doing every PMT question there is

dont forget your functional group tests

phenol : no reaction with Na2Co3 = positive
alkenes : decolourise bromine water
haloalkanes : AgNo3 (white, cream or yellow precipitate)
carbonyl : bradys reagent , if orange then tollens regent (silver = aldehyde, not silver = ketone)

(edited 1 year ago)

Reply 31

zenny1234

9

anyone got the primrose kitten paper for ocr a organic paper 2? thanks

Reply 32

othello03

10

are you all revising the paper 3 content now too?

for most of my exams so far I've been revising for one at a time, but this next week is so busy I might not have much time for paper 3, and a good amount of it's the same as paper 2 (and paper 1).

only things that aren't on paper 2 that I can tell is electrode potentials and redox, lattice enthalpy, acids bases and buffers, synthetic routes and equilibrium, half of which we covered in paper 1 too.

Reply 33

lol2468

Universities Forum Helper

14

Original post by othello03

are you all revising the paper 3 content now too?

for most of my exams so far I've been revising for one at a time, but this next week is so busy I might not have much time for paper 3, and a good amount of it's the same as paper 2 (and paper 1).

only things that aren't on paper 2 that I can tell is electrode potentials and redox, lattice enthalpy, acids bases and buffers, synthetic routes and equilibrium, half of which we covered in paper 1 too.

yh next week is so busy i have an exam everyday except wednesday

Reply 34

cata03

12

Original post by lol2468

yh next week is so busy i have an exam everyday except wednesday

woah that's rough do you take bio chem and maths?

Reply 35

DeeDee2055

10

Original post by lol2468

yh next week is so busy i have an exam everyday except wednesday

Same

Reply 36

othello03

10

Original post by DeeDee2055

Same

Original post by lol2468

yh next week is so busy i have an exam everyday except wednesday

same, who's idea was it to put 3 stem paper 3s in one week 🙃 knowing that many students will likely be taking all 3 subjects,

and 2 chemistry papers 3 days apart what is that about.