Chapter 32, Problem 32.4QAP

Interpretation Introduction

Interpretation:

The sample of PbSO₄ which consist 1-microcurie of Pb-200 and the half-life of this sample is 21.5h. The storage period is to be determined for the activity which is required for the activity which is less than 0.001 microcurie.

Concept introduction:

According to first order of kinetics:

$\ln \left(\frac{N}{N_0}\right)=-\lambda t$

Here, N and N_o are final and initial concentrations, $\lambda$ is decay constant and t is time.

$t_{1/2}\left(half-time\right)=\ln \frac{2}{\lambda }$

Or,

$t_{1/2}=\frac{0.693}{\lambda }$

Here, $t_{1/2}$ is half-life time.