Join TSR now and get all your revision questions answeredSign up now

OCR Chemistry F322~ 4th June 2013~ AS Chemistry Watch

  • View Poll Results: How did you find the exam
    Hard A= 72
    42
    15.22%
    It was okay A= 76
    99
    35.87%
    Easy A= 79
    75
    27.17%
    Very Easy A=82
    60
    21.74%

    Offline

    4
    ReputationRep:
    (Original post by redtortoise)
    Iput c-o and c=o but was really confused, I did put c=c first but got muddled
    I put the same, think you would still get a mark for c=o rather than ester
    Offline

    0
    ReputationRep:
    (Original post by Dizzie31)
    correct.
    the answer is 1640, 240/20= 10 moles 10x 164 to give 1640
    Offline

    0
    ReputationRep:
    (Original post by jacksonmeg)
    I put alkene and carbonyl, will that count ?
    a ketone is a carbonyl, but i'm not 100% sure whether it would be accepted
    Offline

    0
    ReputationRep:
    Could anyone upload the paper itself or the unofficial mark scheme?
    Offline

    0
    ReputationRep:
    (Original post by _Morsey_)
    Are you referring to that one with above 2.5 atmospheric pressure etc? For both i put it to shift left, with absence of catalyst slowing down the rate at which dynamic equilibrium is reached.



    Well it asked for two propagation stages, so i did;

    Initiation: IBr -> I. + Br.

    Propagation Step 1: CH4 + Br. > CH3. + HBr
    Propagation Step 2: CH3. + I2 > CH3I + I.

    Termination: Br + I > IBr etc.



    Thats what i did so i hope it is right :3

    Where does the I2 come from?

    I got

    Initiation: IBr -> I. + Br.

    Propagation Step 1: CH4 + Br. > CH3. + HBr
    Propagation Step 2: CH3. + IBr > CH3I + Br.
    Offline

    0
    ReputationRep:
    (Original post by massi1296)
    the answer is 1640, 240/20= 10 moles 10x 164 to give 1640
    There was 2 moles already in the original equation, not 1.
    10/2 = 5
    so you times it by 5.
    Offline

    7
    ReputationRep:
    For the answer after 820, was it 82?
    Offline

    4
    ReputationRep:
    (Original post by daisyrchds)
    same! seriously need to brush up on my octagon drawing skills though, re-drew it like 4 times
    i couldnt draw a branched 10 C alkane, took me 4 times to get the right amount of C ._.
    Offline

    0
    ReputationRep:
    i put ester c-o and alkene c=c
    Offline

    0
    ReputationRep:
    You can't just predict the Grade boundaries.. I know quiet a few people in my class who hates the paper if you thought it was easy you can't generalise tens of thousands who sat this paper lol
    Offline

    0
    ReputationRep:
    (Original post by dawg)
    Where does the I2 come from?

    I got

    Initiation: IBr -> I. + Br.

    Propagation Step 1: CH4 + Br. > CH3. + HBr
    Propagation Step 2: CH3. + IBr > CH3I + Br.
    i wrote that^
    Offline

    0
    ReputationRep:
    (Original post by Liberty.)
    Please tell me people just drew an octagon on the second page? I felt like an idiot
    i tried to but my octagon ended up more like a circle, so i redrew the cyclooctane putting CH2 at each corner just to emphasise what shape it was supposed to be :L
    Offline

    2
    ReputationRep:
    (Original post by irfymahmood)
    yeppp i did
    There was also a ridiculously small amount of room to draw an ester, with a carbon ring in it, in a puny box.
    Offline

    0
    ReputationRep:
    (Original post by jacksonmeg)
    I put alkene and carbonyl, will that count ?
    I wouldn't think you would get it for carbonyl
    Offline

    0
    ReputationRep:
    (Original post by kingmango)
    For the answer after 820, was it 82?
    yeah 164 / 2 i think
    Offline

    4
    ReputationRep:
    (Original post by Dizzie31)
    There was 2 moles already in the original equation, not 1.
    10/2 = 5
    so you times it by 5.
    isnt it /24 not /20 ?
    Offline

    17
    ReputationRep:
    (Original post by dawg)
    Where does the I2 come from?

    I got

    Initiation: IBr -> I. + Br.

    Propagation Step 1: CH4 + Br. > CH3. + HBr
    Propagation Step 2: CH3. + IBr > CH3I + Br.

    Yeh, i'm not quite sure why i put I2...
    Offline

    0
    ReputationRep:
    (Original post by Dizzie31)
    There was 2 moles already in the original equation, not 1.
    10/2 = 5
    so you times it by 5.
    the +164 was for 2 moles of the N20 formed so you didnt have to divide by 2
    Offline

    0
    ReputationRep:
    (Original post by jacksonmeg)
    isnt it /24 not /20 ?
    the volume was 240
    240/24 = 10
    10/2 = 5 .. Mole ratio
    5 x 164 or whatever = answer
    Offline

    7
    ReputationRep:
    (Original post by Dizzie31)
    yeah 164 / 2 i think
    Sweeeet.
    I'm thinking 82 for an A?
 
 
 
Poll
Should MenACWY vaccination be compulsory at uni?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Quick reply
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.