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A radioactive sample has a mass m, deca...

A radioactive sample has a mass m, decay cosntant `lambda`, and molecular weight M. If the Avogadro number is `N_A`, then
(a) find the initial number of neclei present, (b) find the number of deacyed nuceli after a time t, (c ) find the activity of the sample after a time t,

A

`((mN_(A))/(M))e^(lambdat)`

B

`((mN_(A)lambda)/(M))e^(-lambdat)`

C

`((mN_(A))/(Mlambda))e^(-lambdat)`

D

`(m)/(lambda)(1-e^(-lambdat))`

Text Solution

Verified by Experts

The correct Answer is:
B
Activity `=lambdaN_(o)e^(-lambda t)` where `N_(o)=(N_(A)m)/(M)`
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