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    I'm doing some questions from the "Success Guides" Book, because my Chemistry Prelim is next week and I'm having a problem.

    Q1) Calculate the number of moles in 12.7g of Iodine.
    That's how I've done it:
    Number of Moles=Mass/Formula Mass
    N= 12.7/127
    N= 0.1Mole

    The problem is that on the back of the book it says that the answer is 0.05mole.
    So I'm confused... Am I doing anything wrong?


    I've tried this question a few times and I'm getting the same answer all the time.
    Thanks for any help
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    (Original post by Nessie162)
    I'm doing some questions from the "Success Guides" Book, because my Chemistry Prelim is next week and I'm having a problem.

    Q1) Calculate the number of moles in 12.7g of Iodine.
    That's how I've done it:
    Number of Moles=Mass/Formula Mass
    N= 12.7/127
    N= 0.1Mole

    The problem is that on the back of the book it says that the answer is 0.05mole.
    So I'm confused... Am I doing anything wrong?


    I've tried this question a few times and I'm getting the same answer all the time.
    Thanks for any help
    Iodine is diatomic, which means that it exists in the form of I2 molecules. How do you think this changes your answer?
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    (Original post by fudgesundae)
    Iodine is diatomic, which means that it exists in the form of I2 molecules. How do you think this changes your answer?
    Ohhh!! Got it now
    So it should be
    N=12.7/254
    N=0.05

    Such a stupid mistake I've made...
    I knew that Iodine was diatomic, but I never really though about it when I was doing this question...

    Thanks for your help
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    (Original post by Nessie162)
    Ohhh!! Got it now
    So it should be
    N=12.7/254
    N=0.05

    Such a stupid mistake I've made...
    I knew that Iodine was diatomic, but I never really though about it when I was doing this question...

    Thanks for your help
    np, your welcome. Very easy mistake to make
 
 
 
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