Chapter 20, Problem 20.72SP

Interpretation Introduction

Interpretation:

The age of an igneous rock that contains $\text{3}\text{.35 mmol}$ of $\text{K}$ and $\text{0}\text{.25 mmol}$ of $\text{A}\text{r}$ needs to be determined. The half-life of $\text{K}$ is $\text{1}\text{.25 }\times {\text{ 10}}^{\text{9}}\text{years}$.

Concept introduction:

The nuclear reactions are a type of chemical processes which lead to the formation of some new nuclei with the emission of certain particles. Usually alpha or beta particles, or gamma rays are emitted as a side product with some new daughter nuclei. The nuclei which shows spontaneous decay with time are called as radioactive nuclei. The radioactive decay follows the first order kinetic and the half-life is inversely proportional to the decay constant of the radioactive decay.