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    (Original post by grannyG)
    Lactic acid has a chiral carbon, meaning chemical synthesis produces optical isomers whereas biological synthesis (fermentation) doesn't
    Did you also state the number of possible isomers (2)? They wanted to see the actual number of possibilities in the Jun15 paper.
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    (Original post by sakuraton)
    Got something like that except I got ethanoic acid instead of propanoic acid. 60 was the Mr

    COOH Mr is 45 so there is 15 as remaining which is CH3

    Am I right?

    Unless I calculated the Mr wrong
    I got the Mr as 74 hence proanoic acid
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    (Original post by ShannonD_1697)
    I got something like that too I think! Everyone else seems to have got 2.66g but I have no clue how! Can anyone explain how they did it?
    I got 2.66g - I did it by working out the moles of Phenylamine (which came to 0.03something), then did:

    61% = A/0.03something x 100

    Rearranging gave the moles of A as 0.01something, which I then multiplied by 135 to get 2.66g.

    The logic I used was that we started with 3g of reagent so we couldn't possibly have 7+g of product because that's more than 3g!
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    for the equation of the reduction of the aldehyde to alcohol, would putting OH- as a second product be fine?
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    so is it ethanoic acid or propanoic acid?
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    (Original post by KB_97)
    The unofficial make scheme Google document is a hot mess. I'm gonna put what I got the last structures on here. If you got the same as me thumbs up if not say what you got and we'll see who agrees/disagrees
    New unofficial mark scheme document

    Only selected users can edit, everybody can comment.

    https://goo.gl/gEi388
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    (Original post by lanah_)
    Is there an unofficial mark scheme?
    https://titanpad.com/n3swQKWGYk
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    100% sure the NMR thing was doublet doublet quartet
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    (Original post by adnan_ja01)
    for the equation of the reduction of the aldehyde to alcohol, would putting OH- as a second product be fine?
    Pretty sure the only acceptable form would be:

    Aldehyde + 2[o] --> alcohol
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    Why did the secondary alcohol and ketone have a ch3 group off it? Why couldn't it be a straight chain?
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    (Original post by jadder1224)
    Attachment 549951 did anyone get these ?
    Does it have to have the methyl?! I just did it as straight pentanone :/
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    (Original post by FluffyCommie)
    Pretty sure the only acceptable form would be:

    Aldehyde + 2[o] --> alcohol
    You mean 1 O right?
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    (Original post by gonecrazy)
    so is it ethanoic acid or propanoic acid?
    it's definitely propanoic acid
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    (Original post by CharleaM)
    I got the Mr as 74 hence proanoic acid
    Yeah, everyone else says 74,
    I somehow got the number '60' as Mr which is a Mr for ethanoic acid funny enough so I thought I leave the answer there.
    Yeah, you all probably right, Mr is 74
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    (Original post by A Slice of Pi)
    Did you also state the number of possible isomers (2)? They wanted to see the actual number of possibilities in the Jun15 paper.
    Only because in June 2015 they specifically talked about 25% of the dose being effective (hence four optical isomers).
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    (Original post by jamesgates1)
    Why did the secondary alcohol and ketone have a ch3 group off it? Why couldn't it be a straight chain?
    thats what I did im so confused, it didn't say it was branched or anything either
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    What I remember (there may be mistakes)

    octadec-9,12-enoic acid because it has two trans isomers? which increases level of bad cholesterol.

    Cis-trans isomerism requires different groups attached to each carbon in c=c bond.

    Alcohol and amide.functional groups

    condensation polymer was polyamide and used as fibres in clothing

    Measure Rf values and compare with known Rf values. 2 spots instead of 3 because compounds may not have separated fully

    Polylactic acid could breakdown because ester linkages could be hydrolyses and the stitches could be dissolved because lactic acid could form hydrogen bonds with water using its OH groups.

    Diester made of six carbons and two ester bonds (skeletal formula)
    Percentage yield mass = 2.66g

    formula for peak A was just molecular formula with positive charge
    peak B was CH3CH2NH2 (or something like that) and positive charge

    work out mr of Compound H Mr - 74.
    Compound H: CH3CH2COOH
    For Compound J: (CH3)3CH2OH
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    (Original post by President J)
    It was all under 2 I thought. As it was a 3 Carbons. Doublet, Doublet, Multiplet
    I put the same. Did you have to specify it was a sextet though or is multiplet enough?
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    (Original post by FluffyCommie)
    Pretty sure the only acceptable form would be:

    Aldehyde + 2[o] --> alcohol
    *2[H]
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    (Original post by President J)
    It was all under 2 I thought. As it was a 3 Carbons. Doublet, Doublet, Multiplet
    his/her answer was right i think, cus the middle C was attracted to N fom NH2 and the first one attract to O in OH no?/
 
 
 
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