The half - life of `I^(131)` is 8 days. Given a sample of `I^(131)` at time `t = 0` , we can assert that

Options

A. no nucleus will decay before `t = `4 days
B. no nucleus will decay before `t = 8` days
C. all nuclei will decay before `t = 16` days
D. a given nucleus may decay at any time after `t = 0`

Answer

D

Explanation

Number of nuclei decreases experientially
`N=N_(0)e^(-lambdat)` and Rate of decay `(-(dN)/(dt))=lambdaN`
Therefore, decay process lasts upto `t=oo`. Therefore a given nucleus may decay at any time after `t=0`.