chemistry

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The half-life for the radioactive decay of calcium-47 is 4.5 days.If a sample has an activity of 4.00uCi after 13.5 days, what was the initial activity of the sample?

  • chemistry -

    13.5days/4.5 days = 3 half lives.
    (Activity/23) = 4
    Solve for activity.

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