Question 473424: the half-life of 234u, uranium-234, is 2.52 105 yr. if 98.4% of the uranium in the original sample is present, what length of time (to the nearest thousand years) has elapsed?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! the half-life of 234u, uranium-234, is 252,105 yr. if 98.4% of the uranium in the original sample is present, what length of time (to the nearest thousand years) has elapsed?
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A(t) = Ao*(1/2)^t
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Solve:
0.984Ao = Ao(1/2)^(t/252,105)
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(1/2)^t/252,105 = 0.984
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Take the log of both sides:
(t/252,105) = log(0.984)/log(1/2) = 0.0233
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t = 252,105*0.0233 = 5866.43 years
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Cheers,
stan H.
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