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    Yeah, I don't get why.

    I've tried searching but I need help.
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    The average mass is 35.5, about half of chlorine atoms have a RAM of 35, the other half 36, same with every other decimal one.
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    Thank the lord
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    (Original post by ProbablyJade)
    Thank the lord
    ooPS I DIDN'T FNISH THE POST
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    Oh god my reply is a trainwreck
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    What i meant to say was thank the lord my revision could help me qith this question. Basically the value is an average o all the isotopes taking into account the relative abundance
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    Thanks!

    Good luck to all tomorrow
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    If a element has more than one isotope the relative atomic mass takes account of the relative abundance and RAM mass of each isotope, for chlorine (I think) about 3/4 is Cl-35 and about 1/4 is Cl-37, giving 35.5 overall, though I very much doubt this is necessary to know. The values will be different for each atom obviously, but that is the general idea.
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    (Original post by Jammy Duel)
    The average mass is 35.5, about half of chlorine atoms have a RAM of 35, the other half 36, same with every other decimal one.
    That's incorrect mate :/
    There are two isotopes of Chlorine. Cl-35 and Cl-37. On average 75% of the atoms are Cl-35 and 25% are Cl-37. Therefore on average the atomic number is 35.5.
    35+35+35+37 = 142
    142 / 4 = 35.5
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    (Original post by Jono-Wolf)
    That's incorrect mate :/
    There are two isotopes of Chlorine. Cl-35 and Cl-37. On average 75% of the atoms are Cl-35 and 25% are Cl-37. Therefore on average the atomic number is 35.5.
    35+35+35+37 = 142
    142 / 4 = 35.5
    It's been a while (5 to be precise) but the general point is correct

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    That is the average weighted mass of an atom of chlorine compared to 1/12th the mass of an atom of carbon-12
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    My Chem Teacher should be proud I remembered that
 
 
 
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