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    I was looking at this example in my textbook and saw that there is a small peak at the end for an m/z of 59 and 60 for both propanal and propanone? How did this arise if the relative molecular mass of both molecules are 58?
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    (Original post by scientific222)
    I was looking at this example in my textbook and saw that there is a small peak at the end for an m/z of 59 and 60 for both propanal and propanone? How did this arise if the relative molecular mass of both molecules are 58?
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    The presence of hydrogen isotopes and other isotopes.
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    (Original post by scientific222)
    I was looking at this example in my textbook and saw that there is a small peak at the end for an m/z of 59 and 60 for both propanal and propanone? How did this arise if the relative molecular mass of both molecules are 58?
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    (Original post by charco)
    The presence of hydrogen isotopes and other isotopes.
    Probably due to carbon 13 and other O isotopes rather than H isotopes.
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    (Original post by JMaydom)
    Probably due to carbon 13 and other O isotopes rather than H isotopes.
    This is correct OP, or at least more likely to be correct than Hydrogen isotopes

    This was posted from The Student Room's Android App on my GT-S5830i
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    (Original post by JMaydom)
    Probably due to carbon 13 and other O isotopes rather than H isotopes.
    On consideration, I see that you are quite right. Carbon 13 makes up over 1% of naturally occurring carbon, while deuterium is only about 0.02%.

    My first thought was that as there are many hydrogen atoms in the structures the deuterium would also be significant, but even with butane this only has a minor contribution compared to 13C.

    Thanks for the correction.
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    (Original post by charco)
    On consideration, I see that you are quite right. Carbon 13 makes up over 1% of naturally occurring carbon, while deuterium is only about 0.02%.

    My first thought was that as there are many hydrogen atoms in the structures the deuterium would also be significant, but even with butane this only has a minor contribution compared to 13C.

    Thanks for the correction.
    A pleasure :P
 
 
 
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