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    man i barely think i got 40 on that exam how the hell am i gonna do chem 5.
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    Anyone else 100% genuinely think their grade will be at like 4 grades lower than their predict because of this paper? I wrote like 3 words for the 9 marker, just couldn't make sense of it after so many pages of rubbish, brainf**king questions *criesss*. I think chem5 will be just as bad because it's written by the same people isn't it?
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    How many makrs do you think will I get for syaing the structure of R was

    ch3-o-ch2-ch2-c(ch3)2-oh? Providing all my working is there?
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    (Original post by FormlessBowl)
    The NO3 was a -

    The acid salt had 1 less oxygen and was a +
    Are you sure no2 has a negative charge because in friedl crafts acylation, h2so4 also acts as a base: h2so4 + hno3 ---> no2+ +h2o + hso4-
    And no2+ is formed
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    (Original post by Kay Fearn)
    I think the grade boundaries have to be lower than last years.. unless this year is filled with a bunch of geniuses then I don't see how the grade boundaries can go up. Last year was 85/100 for an A* and the paper wasn't even that tricky..

    The formatting was different, so many tricky one markers here and there that required a lot of time to answer. Pretty sure only the best of the best in the country would have got all the marks from the last question because not only was it disgustingly unfair, it was also at the end of a paper which took quite some time to finish.

    Hoping for 83/100 for A* and like 76/100 for an A
    Hopefully lower! 80/100 A*, 72 A ! ?
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    (Original post by chloeabeki)
    I put: D 1st, E 2nd
    Correct
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    (Original post by Fibsy)
    Damn, I wrote that it can be hydrolysed because it is polar, so it does not have to be removed, unlike the other polymer which is non-polar :/

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    did the same lol. now realise why would you want to hyydrolyse the stitches xD
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    (Original post by Suits101)
    The carboxylic acid just accepts an H+, it doesn't loose an O - where would it go?

    Google the question too, the products are NO3- and CH3COOH2+
    It would go into water, the products you gave definitely work, but I think these do as well. Also where would that H attatch to the ethanoic acid?


    NO3- H2O and CH3C+O makes sense for me, losing an OH with the H of HNO3
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    What did you guys put for the initial rate of reaction questions as to why its used?
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    (Original post by elizabethsophie)
    Could I put Ni and hydrogen with high pressure instead of LiAlH4 for the reduction of the hydroxynitrile to the amine question?
    yeah that's right
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    if i said to distinguish the acyl chloride i add nh3 would that still be right as white misty fumes still produced
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    (Original post by cowie)
    Good point. Perhaps my correction was wrong..
    I completely skipped over the fact that it had to be secondary or primary.. But I cannot see it being any other than a tertiary due to the number of peaks and the data given:/


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    Same as me
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    For the test for the acyl chloride, I put silver nitrate then white ppt. Do I get that or did the silver nitrate have to be acidified/aqueous or something?

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    (Original post by Ginpls)
    Are you sure no2 has a negative charge because in friedl crafts acylation, h2so4 also acts as a base: h2so4 + hno3 ---> no2+ +h2o + hso4-
    And no2+ is formed
    NO2 has a positive charge, NO3 is negative though
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    Mark Scheme pleaseee
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    (Original post by SirRaza97)
    I put silver nitrate in aqueous solution. Forming white ppt for the halo alkane and nothing for the acyl one.
    im pretty sure you can also say for the acyl chloride, using water/ammonia/alcohol/primary amine' would give you Misty fumes
    and for the ketone/ haloalkane; no reaction
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    (Original post by Fibsy)
    Damn, I wrote that it can be hydrolysed because it is polar, so it does not have to be removed, unlike the other polymer which is non-polar :/

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    I think the answer will probably be that the polyester can biodegrade in the wound over time because it is hydrolysed. This means it doesn't have to be removed. Not sure if this is correct though...
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    what did you get for the synthesis question? the five mark to do with compound s and step 3 and 4
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    (Original post by Anno007)
    It's not correct because it doesn't have a triplet peak at 3.1-3.9

    There must be a -COCH2CH2-
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    (Original post by Fibsy)
    Damn, I wrote that it can be hydrolysed because it is polar, so it does not have to be removed, unlike the other polymer which is non-polar :/

    Posted from TSR Mobile
    i wrote that too & i know a few who did. I don't see why it would be wrong
 
 
 
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