Half-life period of a radioactive element is 100 seconds. Calculate the disintegration constant and average life period. How much time will it take for 90% decay?

Explanation

`t^(1//2)=100 sec`
average life period `tau=(1)/(lambda)=(1)/(0.00693)=1.44 sec^(-1)`
`=(2.303)/(0.00693) log (100)/(10)`
`=(2.303)/(0.00693) log 10=332.3 sec`