PELAGIE

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what is the time necessary for 99.9%of the atoms of a radioactive compound to be disintegrated? t½=5times.

  • PELAGIE -

    .001=e^-.692t

    where t is in halfflives...

    ln(.001)=.692t
    -6.91=-.692t
    t=10 halflives...

    Lets look at five halfflives...

    xxx=e^-.692*5
    xxx= 0.031429762 or .97 is gone in five halflives...

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