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    (Original post by 🙈🙈🙉🙊)
    Hi thank you for doing this! if possible could you add in the marks for the questions so i can estimate how badly i did.. also i dont remember a question about how to distinguish between enantiomers?? Did i miss this??
    the electroplie produced was ClCH2CO
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    (Original post by Thisshouldbeapun)
    Currently revising Chem5 after that atrocious chem4

    How much do we need to know about reversible and irreversible cells? Do we need to know the half equations for examples etc or do we only have to know that the reaction can be reversed in rechargeable cells?
    Pretty sure we don't need to know the equations, just how to work out the reactions if they are given in a table.

    Although, considering the last paper, who knows? They might even bung that in there too -_-
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    (Original post by cookiemonster15)
    Pretty sure we don't need to know the equations, just how to work out the reactions if they are given in a table.

    Although, considering the last paper, who knows? They might even bung that in there too -_-
    We need to know catalyst equations (i.e. contact process).
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    Hey guys, for unit 5 born haber cycles I'm just unsure on one thing. Say for example say you're asked to draw the cycle for NaCl can you do the atomisation for Na then the atomisation for 1/2Cl2 then do the first IE or does it have to be Atomisation Na then IE then atomisation 1/2Cl2? Thanks
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    (Original post by berries366)
    Hey guys, for unit 5 born haber cycles I'm just unsure on one thing. Say for example say you're asked to draw the cycle for NaCl can you do the atomisation for Na then the atomisation for 1/2Cl2 then do the first IE or does it have to be Atomisation Na then IE then atomisation 1/2Cl2? Thanks
    As standard, it should really be atomisation of 1/2Cl2, followed by atomisation of Na followed by first IE of Na.

    But mark schemes will always allow them in either order, as long as you get the highest potential energy products at the top of the cycle.
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    the ethanal and ethanol reaction was nucleophillic addition elimination ?
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    (Original post by SubwayLover1)
    the ethanal and ethanol reaction was nucleophillic addition elimination ?
    No, just nucleophilic addition.

    What was being eliminated? We ended up with a diol I seem to remember.

    EDIT: Scrap that, it was hemiacetal, which is a hydroxy ether, but still nucleophilic addition.
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    (Original post by Cadherin)
    No, just nucleophilic addition.

    What was being eliminated? We ended up with a diol I seem to remember.

    EDIT: Scrap that, it was hemiacetal, which is a hydroxy ether, but still nucleophilic addition.
    wasn't one of the hydrogens lost on the oxygen ? because youv'e gone from an alcohol to an ether ?
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    (Original post by SubwayLover1)
    wasn't one of the hydrogens lost on the oxygen ? because youv'e gone from an alcohol to an ether ?
    Yes, but this isn't a leaving group, this is only being picked up by the leftover base (i.e. O+) and donating an electron pair to O+.

    No C=O double bond was re-formed by kicking out a leaving group: O:- accepted a proton to form the hydroxyl group.
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    (Original post by Cadherin)
    Yes, but this isn't a leaving group, this is only being picked up by the leftover base (i.e. O+) and donating an electron pair to O+.

    No C=O double bond was re-formed by kicking out a leaving group: O:- accepted a proton to form the hydroxyl group.
    true ! the naming bit was a seperate question wasn't it ?

    I think I did the mechanism correct!
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    (Original post by RME11)
    Was a tough paper, but I can't see the AQA doing much - the questions about lidocaine/polymers for stitches etc were how science works questions that required thinking outside of the box, they've been pretty on point with the HSW stuff in the past couple of years..
    I agree with this, im so frustrated with myself because instead of using knowledge i already knew, i got too intimidated by the strangeness of the questions and started to think WAY outside the box(plus the thinking time was strict on this paper), i found myself crossing out a few right answers to put in wrong ones
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    https://www.facebook.com/groups/148389988911787/
    join
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    (Original post by Alevels16)
    Do you think you can put NaOH with an acid catalyst for the hydrolysis of the Estee???Also does anyone remember the moles we were given when we had to work out KC that got an answer of 9.09x10-3 I know one was 0.58 another was 3.76 I think???? What were the other two?
    i put naoh aq with acid catalyst too, the h2o and acid catalyst would break the ester up and then the nah would form the sodium ethanoate or whatever it was
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    (Original post by High Stakes)
    Step 3 was a substitution question to go from Br to a CN group. So I said KCN aqueous and alcohol.

    The final step was reduction, so Hydrogen & Nickel Catalyst.
    I was going to put KCN aqueous and alcoholic, but in the question it said "one condition" so I went with alcoholic. Not sure what kind of answer they were looking for there, did they want aqueous and alcoholic, or aqueous or alcoholic?
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    (Original post by thomaarrss)
    i put naoh aq with acid catalyst too, the h2o and acid catalyst would break the ester up and then the nah would form the sodium ethanoate or whatever it was
    Yeah that's what I thought but now I'm thinking an acid catalyst will form the carboxylic acid not the carboxylic salt because when the Salt is formed the acid catalyst will turn it to a CA (
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    Can anyone confirm?

    I put heat under reflux to separate alcohol is this right?

    Was nucle add elim the answer to any questions?
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    (Original post by Alevels16)
    Yeah that's what I thought but now I'm thinking an acid catalyst will form the carboxylic acid not the carboxylic salt because when the Salt is formed the acid catalyst will turn it to a CA (
    Conditions are a dilute strong base, heat under reflux and conc h2so4 catalyst and the base had to be NaOH also question said conditionS hence I think the answer should've been:

    Dilute NaOH, HUR and conc H2SO4 catalyst but in the past they've been generous with putting dilute/conc

    Your reasoning is right but using what I said/you said you will produce the alcohol and sodium salt which is what we needed. Only if you used a strong acid would you not et the sodium salt but get a carboxylic acid instead

    (Original post by Fibsy)
    I was going to put KCN aqueous and alcoholic, but in the question it said "one condition" so I went with alcoholic. Not sure what kind of answer they were looking for there, did they want aqueous and alcoholic, or aqueous or alcoholic?
    Markschemes in past have 'aqueous or alcoholic' but I put aqueous ethanol because it covers both answers.
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    (Original post by MuaazAnsari)
    the electroplie produced was ClCH2CO
    Thank you finally someone who agrees!
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    (Original post by Suits101)
    Conditions are a dilute strong base, heat under reflux and conc h2so4 catalyst and the base had to be NaOH also question said conditionS hence I think the answer should've been:

    Dilute NaOH, HUR and conc H2SO4 catalyst but in the past they've been generous with putting dilute/conc

    Your reasoning is right but using what I said/you said you will produce the alcohol and sodium salt which is what we needed. Only if you used a strong acid would you not et the sodium salt but get a carboxylic acid instead



    Markschemes in past have 'aqueous or alcoholic' but I put aqueous ethanol because it covers both answers.
    Sounds right but I didn't put heat under reflux
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    Grade boundaries anyone? For an A* and an A?
 
 
 
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