chemistry

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What is the half-life of an isotope if it decays to 12.5% of its radioactivity in 18 minutes?

  • chemistry -

    ln(100/12.5) = k*18
    Solve for k, then
    k = 0.693/t(sub>1/2.
    Solve for t1/2.

  • chemistry corr'n -

    k = 0.693/t1/2

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