SOLUTION: Chemistry. The decay rate of krypton-85 is 6.3% per year. What is its half-life?

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Question 328587: Chemistry. The decay rate of krypton-85 is 6.3% per year. What is its half-life?
Answer by stanbon(75887) About Me  (Show Source):
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The decay rate of krypton-85 is 6.3% per year. What is its half-life?
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If it decays 6.3% each year 93.7% is preserved each year.
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A(t) = Ao*(1-0.063)^t
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(1/2)Ao = Ao(0.937)^t
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0.937^t = 0.5
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Take the log and solve for "t":
t = [log(0.5)]/[log(0.937)]
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t = 10.65 years
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Cheers,
Stan H.