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    (Original post by TJB12345)
    Just going to throw out some numbers that are on my calculator and see if they ring a bell with anyone:

    2.9 x10^-2
    -1099
    104
    2.12
    3.43
    13.03
    10.68

    Anyone recognise these?
    Yeah I have a load of those numbers
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    i did 0.05-0.04 so 0.01 for H+ and 0.04 for A- in buffer calculation, how many marks wud i lose?
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    (Original post by pentsr)
    i did 0.05-0.04 so 0.01 for H+ and 0.04 for A- in buffer calculation, how many marks wud i lose?
    1 or 2 at most; you'd get follow on marks.
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    (Original post by Noah T)
    No need for this dude, we're all A level chemists, no one who's made it here is bad at chemistry. Everyone's just finished an exam today, try and understand that for some people it didn't go as well as it could have done at no fault of their own.
    h

    So we'll assume you're going to Oxford/Cambridge then. Happy for you. In the mean time stop shutting others down as a way to fuel your own ego. Everyone on this thread has studied chemistry- everyone has a topic they like and others they hate. The paper might have been jam packed full of your favourite topic, yet equally filled with someone else's nemesis. No one is grateful for your comment so keep it to yourself
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    (Original post by jirachi)
    1 or 2 at most; you'd get follow on marks.
    thanks!
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    (Original post by chelswaldx)
    h

    So we'll assume you're going to Oxford/Cambridge then. Happy for you. In the mean time stop shutting others down as a way to fuel your own ego. Everyone on this thread has studied chemistry- everyone has a topic they like and others they hate. The paper might have been jam packed full of your favourite topic, yet equally filled with someone else's nemesis. No one is grateful for your comment so keep it to yourself
    Realised I've quoted the wrong guy here but you know who you are lmao
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    (Original post by jirachi)
    1 or 2 at most; you'd get follow on marks.
    hey do you remember the correct salt and acid moles/concs?
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    I'd like to add that this paper was deceptively easy. I go to a grammar school and there's one question that pretty much everyone I've talked to got wrong, even though they thought they got the correct answer at first.

    I predict ~ 75 for an A and 83 for A*
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    was the first question Cu(NH3)6 or Cu(NH3)4?
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    (Original post by alu4days)
    hey do you remember the correct salt and acid moles/concs?
    [HNO2] = 0.04 mol dm-3 and [NO2-] = 0.05 mol dm-3, I believe.
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    (Original post by jirachi)
    I'd like to add that this paper was deceptively easy. I go to a grammar school and there's one question that pretty much everyone I've talked to got wrong, even though they thought they got the correct answer at first.

    I predict ~ 75 for an A and 83 for A*
    Which questiom would that be?
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    (Original post by four4)
    Which questiom would that be?
    The oxidation/reduction of Cr3+ redox systems one. Everyone I talked to listed all of the redox systems (so like 1 with 2, 2 with 3, 2 with 4, 2 with 5, etc.) They'd lose only 2 marks or so, at most, though.

    And quite a few people got the starch question wrong (myself included, I put phenolphthalein).
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    Instead of revising for bio, I am on here trying to find an unofficial markscheme 😂
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    (Original post by jirachi)
    [HNO2] = 0.04 mol dm-3 and [NO2-] = 0.05 mol dm-3, I believe.
    since the acid was 0.04 moles and the base was 0.05 moles, this shows that the acid is limiting so the moles of salt is 0.04?
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    (Original post by alu4days)
    since the acid was 0.04 moles and the base was 0.05 moles, this shows that the acid is limiting so the moles of salt is 0.04?
    The concentration of NaNO2 (or whatever the base was), was 0.05 mol dm-3, and that dissociates completely to form 0.05 mol dm-3 of NO2- ions. So the concentration of HNO2 remains at 0.04 mol dm-3 because the conjugate base doesn't form from it.
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    (Original post by jirachi)
    The concentration of NaNO2 (or whatever the base was), was 0.05 mol dm-3, and that dissociates completely to form 0.05 mol dm-3 of NO2- ions. So the concentration of HNO2 remains at 0.04 mol dm-3 because the conjugate base doesn't form from it.
    :/ you reckon I might get ECF?
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    (Original post by alu4days)
    :/ you reckon I might get ECF?
    Think so, the next steps were to calculate Kc and use the correct unit so that's 2 marks at least that you can still get, maybe even 3 out of the 4.
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    those who found this paper easiest paper they have ever sat since year 7 please make the mark scheme or shut up
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    (Original post by jirachi)
    Think so, the next steps were to calculate Kc and use the correct unit so that's 2 marks at least that you can still get, maybe even 3 out of the 4.
    wasn't it to calculate pH?
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    (Original post by pentsr)
    i did 0.05-0.04 so 0.01 for H+ and 0.04 for A- in buffer calculation, how many marks wud i lose?
    I did this, you'd probs still get 2 I'd expect
 
 
 
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