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    Hi can anybody please post a step by step reply as to how to answer this question:

    The mass spectrum of CH3Br contains two molecular ion peaks of equal abundance with m/z values of 94 and 96. Deduce the number of molecular ion peaks in the spectrum of the compound CH2Br2. Give their relative abundances and the m/z value of the molecular ion peaks.

    Thank you xx
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    (Original post by xgoldenx)
    Hi can anybody please post a step by step reply as to how to answer this question:

    The mass spectrum of CH3Br contains two molecular ion peaks of equal abundance with m/z values of 94 and 96. Deduce the number of molecular ion peaks in the spectrum of the compound CH2Br2. Give their relative abundances and the m/z value of the molecular ion peaks.

    Thank you xx
    Basically the question is telling you that bromine exists as two isotopes 79-Br and 81-Br

    If there are two bromine atoms in the molecule how many different combinations of bromine atoms are there possible.

    As the probability of 79-Br and 81-Br are equal, work out the relative probability of each combination occurring. (you can treat them like two coins, heads and tails)
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    (Original post by charco)
    Basically the question is telling you that bromine exists as two isotopes 79-Br and 81-Br

    If there are two bromine atoms in the molecule how many different combinations of bromine atoms are there possible.

    As the probability of 79-Br and 81-Br are equal, work out the relative probability of each combination occurring. (you can treat them like two coins, heads and tails)
    I always come to these kinds of threads thinking I'll be able to answer the question really well, and then I see someone has already posted an answer that's a lot clearer and better explained than mine would've been.

    Well done sir/ madam.
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    (Original post by I'mBadAtMaths)
    I always come to these kinds of threads thinking I'll be able to answer the question really well, and then I see someone has already posted an answer that's a lot clearer and better explained than mine would've been.

    Well done sir/ madam.
    especially when that someone is charco... :yep:
 
 
 
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