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AQA A-level Chemistry paper 2 7405/2 Unofficial Markscheme Watch

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    (Original post by Sajmeister99)
    For the 1,3 dinitrobenzene where it asked you for electrophilic substitution, does anyone remember the exact question? Did they ask you to form 1/3 dinitrobenzene from benzene or 1-nitrobenzene?
    it was one-nitrobenzene
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    (Original post by Hassankhan2405)
    What course did you apply to? medicine?
    Chemical engineering fam
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    (Original post by student1099)
    no offence but do you always type like that...
    No offence you're wet. My man thinks it's fine with a dusty "no offence"
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    (Original post by ashly.alava)
    I agree my chem teacher agrees too although he's not brilliant but yeah I think you are right
    i got egf too as in F the nitrogen was just attached to an alkyl group
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    (Original post by Bence9912)
    it was one-nitrobenzene
    Oh thank you soo much!! You made my day.
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    (Original post by 1anonomous)
    Thanks- so what do u think grade boundaries will be like for this paper?
    Well, if we are being realistic lower than old spec, but not by too much.The only questions that were really different from the old spec were those involving DNA, the hydrogen bonding in bases and maybe thise wierd NMR questions,but we don't have coursework to help us out anymore either so I would say around 70-75% for an A*, and around 65-70% for an A.I am inclined to believe that the it will be near the upper end of those ranges.
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    (Original post by Sajmeister99)
    Oh thank you soo much!! You made my day.
    Omg I did electrophilic sub ON 1 3 dinitro benzene I need to start reading questions 😫
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    (Original post by brumtown0121)
    Loool nah man I'm just about surviving the year

    And Birmingham, Newcastle, Leeds, UCL and Manchester lol
    Similiar to me fam you better not be cheating by applying to the BTEC Manchester and Birmigham. A levels are on a another level. Im going to have to go through clearing..... Good luck for the rest of your exams my homie.
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    (Original post by chemspaz)
    Omg I did electrophilic sub ON 1 3 dinitro benzene I need to start reading questions 😫
    Oh unlucky man. Don't worry, I screwed up the 3 step synthesis. I cannot believe it was just free radical substitution
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    (Original post by brumtown0121)
    Was I the only one who talked about distinguishing K L M N separately???? I gave each letter its own test, cos I swear question said they were in separate test tubes and to my knowledge it wasn't a mixture, it was just separate solutions of each letter, one of u clever clogs lemme know what's up
    omds i did the same as well. I thought thats how these questions work.
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    (Original post by Khanman123)
    Jeeez, I messed up that last question man. 145mg for that other one. I got 15.8 or suttin like that for Ea.
    i think i got 15.8 too
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    (Original post by Sajmeister99)
    Oh unlucky man. Don't worry, I screwed up the 3 step synthesis. I cannot believe it was just free radical substitution
    Yh, I guess everyone's gonna lose a few marks one way or another. I'll actually read the questions for Paper 3 lol
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    (Original post by Khanman123)
    Jeeez, I messed up that last question man. 145mg for that other one. I got 15.8 or suttin like that for Ea.
    I originally got 15.8 but youve made the same mistake I did, It gave you the value of lnA not of just A (16.9 i think??) so you didnt need to place this into ln...took me a few attempts to spot this error, I eventually got 50.7kJmol-1
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    (Original post by Emz99)
    Similiar to me fam you better not be cheating by applying to the BTEC Manchester and Birmigham. A levels are on a another level. Im going to have to go through clearing..... Good luck for the rest of your exams my homie.
    Looool nahhh man allow the btec ones, they rah pay you 9k a year to attend, it's mad still, anyways think positively ygm, there's always a way in life to achieve anything you endeavour - man like me talking English for once lol, good luck fam
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    (Original post by emilyvrl)
    Step 1 :
    H2SO4 + HNO3 --> H2NO3 + HSO4

    Step 2 :
    Methylbenzene + HNO3 --> methylnitrobenzene + H2O ( conc H2SO4 catalyst )

    Step 3 :
    MethylNitrobenzene + 6[H] --> methylphenylamime + 2H2O ( Sn/HCl catalysts , room température )

    Okay so that's all I did for the very last question . It makes sense to me but I have no clue if it's right . Any opinions ?
    This is what i did:
    Step 1: free rad subs - Br2 and uv light
    step 2: KCN alcoholic
    Step 3: reduce using Ni catalyst and H2 under high temp and high pressure
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    was it serine at a high or low ph? I remember writing COO- but I'm doubting myself now
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    what are the grade boundaries usually like for chem?
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    (Original post by Bence9912)
    it was one-nitrobenzene
    i swear it asked you to make 1,3 di nitro benzene from nitrobenzene ?
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    (Original post by chemspaz)
    Omg I did electrophilic sub ON 1 3 dinitro benzene I need to start reading questions 😫
    Same omg how many marks was that question? im so annoyed i made such a silly mistake
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    (Original post by newera)
    was it serine at a high or low ph? I remember writing COO- but I'm doubting myself now
    Yes, that i what i wrote as in high ph, i swear there is loads of oh ions, so serine will act acidic
 
 
 
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