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The Atomic Mass

  1. Feb 3, 2004 #1
    The Atomic Mass!!

    Hello, I have a problem of getting the answer of this question and I still don't understand it. The question is

    What I though is that the answer is "1,700,000,000,000,000,000" and I thought it's same as when we say we have a red apple and how many red apples are in 1700000000 red apples. That's sounds strange and probbly wrong i'm not sure . Do we have to do this -> 1,700,000,000,000,000,000 / 69.72 to get the answer?

    ... Any ideas???
  2. jcsd
  3. Feb 3, 2004 #2


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    Find the atomic mass of the two gallium isotopes.

    69.72 =[(number of Isotope 1)(atomic mass)+(number of Isotope 2)(atomic mass)] / 1,700,000,000,000,000,000

    Solve so that you obtain (number of isotope 1)/(number of isotope 2)

    Try to do it yourself first.

    The above will be the proportion. For example if the proportion is 1/3 the total percentage of a particular isotope will be either 1/4 or 3/4. Multiply this percentage with 1,700,000,000,000,000,000.
    Last edited: Feb 3, 2004
  4. Feb 3, 2004 #3
    Thanks alot for your help :smile:
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