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    can anyone help with this question?:

    an aldehyde has the molecular formula C5H10O.

    Its h nmr spectrum contains a doublet at delta= 0.9ppm with relative peak area of 6 compared with the aldehyde proton.

    analyse this information to deduce the structure of the aldehyde. explain your reasoning

    thanks
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    (Original post by Princess_perfect786)
    can anyone help with this question?:

    an aldehyde has the molecular formula C5H10O.

    Its h nmr spectrum contains a doublet at delta= 0.9ppm with relative peak area of 6 compared with the aldehyde proton.

    analyse this information to deduce the structure of the aldehyde. explain your reasoning

    thanks
    relative peak (compared to CHO) are means there are six equivalent hydrogen atoms...

    any ideas?
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    (Original post by charco)
    relative peak (compared to CHO) are means there are six equivalent hydrogen atoms...

    any ideas?
    oh yeah... benzene.

    but wouldn't there only be 5 equivalent h atoms because the CHO group has replaced one of them?
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    (Original post by Princess_perfect786)
    oh yeah... benzene.

    but wouldn't there only be 5 equivalent h atoms because the CHO group has replaced one of them?
    There are only five carbons in total!!!! How can is be C6H5- ?

    The only way you can have six equivalent hydrogens is two -CH3 groups. If these form a doublet then they're both adjacent to a CH...

    Try again
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    (Original post by charco)
    There are only five carbons in total!!!! How can is be C6H5- ?

    The only way you can have six equivalent hydrogens is two -CH3 groups. If these form a doublet then they're both adjacent to a CH...

    Try again
    the closest i can get is:

    (ch3)ch(ch3)cho i don't know how to get the other carbon and other three hydrogens
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    isnt it
    c double bond o for the aldehyde group at the end, the ch2 and then a c with 2 methyl groups and 1 h attached to it :/
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    so altogether there is 4 environments. i thinkk
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    (Original post by sssm)
    isnt it
    c double bond o for the aldehyde group at the end, the ch2 and then a c with 2 methyl groups and 1 h attached to it :/
    i think that's right. thanks
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    So is the answer 3-methylbutanal?
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    i think its 3-methylbutanal

    yup
    i think thats what the answer is.
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    wouldnt it be 2methylbutanal.
    if your counting so its the smallest number is would be 2 right?
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    http://www.docbrown.info/page15/Image1896.gif
    3 methyl butanal

    http://www.docbrown.info/page15/Image1894.gif
    2 methyl butanal

    i think it is 3 methyl butanal, you count from the functional group?
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    i defo got the one under 3 methyl butanal.
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    The important thing is to understand why...

    (CH3)2CHCH2CHO

    Do you?
 
 
 
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