chemistry

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Strontium-90 decays through the emission of beta particles. It has a half-life of 29 years. How long does it take for 80% of a sample of strontium-90 to decay?
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  • chemistry -

    k = 0.693/t1/2
    ln(No/N) = kt

    Use No = 100
    N = 20
    k from above
    solve for t in years.

  • chemistry -

    27

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