SOLUTION: Suppose you have a sample of phosphorus-32 that has only 3.1 percent of its original radioactivity, how old is this sample if its half-life is fourteen days? N/N0=.031

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Question 481948: Suppose you have a sample of phosphorus-32 that has only 3.1 percent of its original radioactivity, how old is this sample if its half-life is fourteen days?
N/N0=.031

Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
Suppose you have a sample of phosphorus-32 that has only 3.1 percent of its original radioactivity, how old is this sample if its half-life is fourteen days?
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0.031No = No(1/2)^(t/14)
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0.031 = (1/2)^(t/14)
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(t/14) = log(0.031)/log(1/2)
t/14 = 5.0116
time = 70.1622 days
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Cheers,
Stan H.

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