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Radioactive isotopes

  1. Dec 11, 2006 #1
    I just want to make sure I just formulted a valid statement:

    Two samples contain different radioactive isotopes. It is not possible for these samples to have the same activity because each isotope radioactive isotopes change their composition at different rates.

    Anyone able to agree with this statement or counter it, saying why it is possible for these samples to have the same activity?
  2. jcsd
  3. Dec 11, 2006 #2


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    Are the samples pure, or are (for instance) the radioactive isotopes mixed with inert isotopes?
  4. Dec 11, 2006 #3
    I think I'm just talking about pure samples lol. Basically I just needed to make a statement on whether or not it's possible for two samples containing different radioactive isotopes to have the same activity and explain a bit.
  5. Dec 11, 2006 #4
    It is conceivable that there are pairs of isotopes with identical decay rates.

    Regardless, for any two isotopes, it should nonetheless be possible to prepare two samples with identical activity (at a given moment) just by having different quantities.

    These won't maintain identical activity, since the little sample is burning up quickly whilst the big slowly-decaying (longer half-life) sample will maintain its rate much longer.

    Uh.. FlipStyle, aren't you concerned your instructor / peers will see this site?
    Last edited: Dec 11, 2006
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