Chemistry

If it takes 45 days for 80.0 mg of a particular radioactive isotope to decay to 10.0 mg what is its half-life?

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asked by Kelly
  1. 80(1/2)^t = 10
    (1/2)^t = 1/8
    t = 3

    so, 45 days is 3 half-lives

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    posted by Steve

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