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vichka [17]
4 years ago
13

Americium-241 is used in some smoke detectors. it is an alpha emitter with a half-life of 432 years. how long will it take in ye

ars for 45.0 % of an am-241 sample to decay?
Chemistry
1 answer:
kolbaska11 [484]4 years ago
4 0
The amount of substance at a certain time t, At, with half-life of h is determined by the equation,
                          At = (Ao)(0.5)^(t/h)
where Ao is the original amount. 
From the given,
                         At/Ao = 0.45 = (0.5)^(t/432)
The value of t from the equation is 497.67 years. 
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