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    tests for acyl chloride- can you use sodium hydrogen carbonate?
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    (Original post by zombaldia)
    I agree the question was dodgy because it didn't state I2 wasn't in RDS, it just asked you to suggest why. It could have been that I2 was in massive excess in which case it would appear to be pseudo order. This was a very tricky question I thin.... I think it's safe to say propanone was pseudo order, so would appear to be zero order, but they may still include in rate equation? In which case it'd just be the same? However I think this would be very strange of AQA... I went with r=k[h+] in the end using the logic I2 not in rds and the ketone is in massive excess so won't affect the rate... Hopefully this is right!
    It may be possible that they allow more than one answer (but not one with iodine) I would have thought. If lots of candidates offer alternatives (which is possible) and as long as you justify it properly, this may be the case.

    Or M1 may be dependent on a properly explained M2.
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    (Original post by TJ_gym)
    Will you get marks for this way??
    I can't see why not - it's the most valid method I've seen so far.

    Besides, it was a unit 1 synoptic question and I think AQA were hinting at that by the way they asked the question.
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    (Original post by Medlad101)
    lidocaine is basic so adding hydrogen chloride would make it a neutral pH so that it wouldnt harm the patient, thats what i put
    Omg that's what I put too! Literally thought I was the only one,I mentioned it not being too strong a base so it doesn't denture your enzymes
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    (Original post by Cadherin)
    It may be possible that they allow more than one answer (but not one with iodine) I would have thought. If lots of candidates offer alternatives (which is possible) and as long as you justify it properly, this may be the case.

    Or M1 may be dependent on a properly explained M2.
    I agree, seems logical they will award M1 based on reasoning of M2
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    For the Cl containing ketone and acyl chloride test, although both have a Cl so you would think both would form a white ppt with silver nitrate... is the haloalkane reactive enough to release the Cl?
    Do you not have to release the halide first with aqueous NaOH for that to happen?

    ... just me trying to defend my pitiful case for 3 more marks

    Posted from TSR Mobile
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    (Original post by zombaldia)
    I agree, seems logical they will award M1 based on reasoning of M2
    Mind you, I think I had a VERY lucky guess of the last compound on the 9 mark analysis, as I wrote down as much info as I could and sort of half-guessed it with 30 seconds left.
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    (Original post by emilies18)
    tests for acyl chloride- can you use sodium hydrogen carbonate?
    Yh you can
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    i think this is the answer for the last question
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    Could we say that i2 wasnt included as it was a solid?
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    (Original post by Fibsy)
    For the Cl containing ketone and acyl chloride test, although both have a Cl so you would think both would form a white ppt with silver nitrate... is the haloalkane reactive enough to release the Cl?
    Do you not have to release the halide first with aqueous NaOH for that to happen?

    ... just me trying to defend my pitiful case for 3 more marks

    Posted from TSR Mobile
    Yes, that is exactly what I put and it is right.

    The RCH2Cl bond (C-Cl) is not polar enough without a strong base catalyst like NaOH. So, if you put "AgNO3" without NaOH, you will get full marks for white precipitate with the acyl chloride and no change with the RCH2Cl. If you put "AgNO3 with NaOH", CE=0.
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    (Original post by Saldudsjen123)
    Omg that's what I put too! Literalist ly thought I was the only one,I mentioned it not being too strong a base so it doesn't denture your enzymes
    thank god hahahaha, it sounds right but we'll have to wait and see
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    (Original post by shirrushtii)
    i think this is the answer for the last question
    Yup
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    (Original post by emma_1111)
    Could we say that i2 wasnt included as it was a solid?
    Not in rate determining step
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    (Original post by MuaazAnsari)
    Yh you can
    I put with ammonia misty fumes are given off is this wrong?
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    Does anyone else feel really let down? I have spent the past months revising hard and had done every past paper averaging about 84/85 so was really motivated to go and smash this and then AQA give us this horrendous paper... I think I've lost so many simple marks and now I feel really unmotivated to revise for CHEM5 because if they're this horrible again then anything I revise isn't going to come up
    Chances of getting into uni are now very slim as I needed to average low As in both papers and think I've got low C/high D for CHEM4
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    (Original post by shiney101)
    Is anyone making a change.org petition?
    I was literally on the website contemplating 🤔 We need a strong, balanced argument.
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    (Original post by Fibsy)
    Is this for the acyl chloride and the ketone? I put silver nitrate too, but now I realise that there was a chlorine on both of them so silver nitrate would produce a white ppt with both :/

    Posted from TSR Mobile
    there was a similar question on the jan 2007 paper, agno3, acycl chloride white ppt formed , vigorous. with the ch2cl one, could either say no visible change or slow white ppt formed
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    Hey what did everyone tick for the number of C peaks? was it 9?
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    (Original post by shirrushtii)
    i think this is the answer for the last question
    I thought there was a ch2-o-ch3 group
 
 
 
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