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    the CH3 groups on the diagram are not counted as methyl groups, how come?
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    I count them as methyl groups, and that's all that should matter.
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    (Original post by Straighthate)


    the CH3 groups on the diagram are not counted as methyl groups, how come?
    They are methyl groups. /thread
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    (Original post by langlitz)
    They are methyl groups. /thread
    in the mark scheme for a paper they are not
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    (Original post by Straighthate)
    in the mark scheme for a paper they are not
    Well, they are. So, either the mark scheme was wrong, or the question was worded such to preclude writing "Me" in place of "CH3", or they just decided to put the equivalent "CH3" as the answer.
    If it doesn't say "Do NOT accept "Me" or an unlabelled terminal skeletal arm in place of a terminal "CH3" label" then I wouldn't be worried; it all means the same thing.
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    (Original post by Straighthate)
    in the mark scheme for a paper they are not
    And is this reasoned by your paper? as the people said it above, they are methyl groups. I can't see another ones.
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    Look at the mark scheme again
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    (Original post by Infraspecies)
    Well, they are. So, either the mark scheme was wrong, or the question was worded such to preclude writing "Me" in place of "CH3", or they just decided to put the equivalent "CH3" as the answer.
    If it doesn't say "Do NOT accept "Me" or an unlabelled terminal skeletal arm in place of a terminal "CH3" label" then I wouldn't be worried; it all means the same thing.
    But why functional groups like methyl groups should be precluded or regarded as equivalent, if they exist?
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    (Original post by Kallisto)
    But why functional groups like methyl groups should be precluded or regarded as equivalent, if they exist?
    I don't know what you're trying to say, reword that please.
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    They are methyl groups - if the markscheme says otherwise... then its wrong
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    (Original post by Infraspecies)
    I don't know what you're trying to say, reword that please.
    Then I have not understand your statement before. I was confused to be honest. What did you mean when you say 'to put the equivalent "CH3" as the answer'? that CH3 should not regarded as a functional group by a paper? I don't get it.
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    (Original post by Kallisto)
    And is this reasoned by your paper? as the people said it above, they are methyl groups. I can't see another ones.
    http://www.ocr.org.uk/Images/135165-...lysis-june.pdf

    question 3ci, it asks you what functional groups are present in this molecule, as shown by the mark scheme you LOSE mark if you mention that there is a methyl group
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    (Original post by Straighthate)
    http://www.ocr.org.uk/Images/135165-...lysis-june.pdf

    question 3ci, it asks you what functional groups are present in this molecule, as shown by the mark scheme you LOSE mark if you mention that there is a methyl group
    Methyl groups arent fuctional groups

    Functional groups are responsible for the reactions of a compound. Eg alkene

    Posted from TSR Mobile
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    (Original post by brother aldi)
    Methyl groups arent fuctional groups

    Functional groups are responsible for the reactions of a compound. Eg alkene

    Posted from TSR Mobile
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    (Original post by Straighthate)
    http://www.ocr.org.uk/Images/135165-...lysis-june.pdf

    question 3ci, it asks you what functional groups are present in this molecule, as shown by the mark scheme you LOSE mark if you mention that there is a methyl group
    See, you took the question out of context. When a question asks you to name the functional groups, you're not supposed to name every single group of atoms in the molecule, only the "special" or specific ones that give the molecule its particular properties and/or reactivity.

    So for this molecule I'd say the functional groups are the lactone and the alcohol.
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    (Original post by Straighthate)
    http://www.ocr.org.uk/Images/135165-...lysis-june.pdf

    question 3ci, it asks you what functional groups are present in this molecule, as shown by the mark scheme you LOSE mark if you mention that there is a methyl group
    Yeah, but I don't get it why this should be wrong. The whole molecule has three CH3-group and one OH-group. And I can't see a plausible reasoning.

    But perhaps these groups are regarded just as parts of the molecule? no, that is senseless.

    EDIT: okay, I have read the posted statements above. So I see the sense.
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    (Original post by Straighthate)
    http://www.ocr.org.uk/Images/135165-...lysis-june.pdf

    question 3ci, it asks you what functional groups are present in this molecule, as shown by the mark scheme you LOSE mark if you mention that there is a methyl group
    I also think it's slightly oversimplified to call the C=O next to the O just an ester, when it's actually a lactone (cyclic ester). A lactone is more reactive than a normal ester because in a normal ester there is additional stabilisation in the Z conformation provided by the overlap of the oxygen lone pair and the C-O sigma anti bonding orbital of the C=O bond.
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    (Original post by brother aldi)
    Methyl groups arent fuctional groups

    Functional groups are responsible for the reactions of a compound. Eg alkene
    Just to hedge my bet: functional groups in the narrower sense are the ones who are reacting with each other and forming a bound between molecules? so the NH2- and COOH-group of amino acids in charged states for instance?
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    (Original post by EdmundWoodstock)
    I also think it's slightly oversimplified to call the C=O next to the O just an ester, when it's actually a lactone (cyclic ester). A lactone is more reactive than a normal ester because in a normal ester there is additional stabilisation in the Z conformation provided by the overlap of the oxygen lone pair and the C-O sigma anti bonding orbital of the C=O bond.
    thi is A2 though
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    (Original post by Straighthate)
    thi is A2 though
    I know, sorry, I just can't resist correcting errors or vagueness, given I'm studying Natural Sciences at Uni
 
 
 
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