Chapter 20, Problem 83AP

Interpretation Introduction

Interpretation:

The number of atoms of radioactive ${}^{131}\text{I}$ is to be calculated.

Concept introduction:

The rate of decay for a particular isotope is given by the rate law expression, that is as follows:

$\text{Rate = }\lambda \text{N}$

Here, $\lambda$

is the rate constant for the radioactive decay and $\text{N}$ is the number of atoms in the sample.

Nearly all the radioactive decay is of the first order and its rate constant is given as follows:

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

Here, $t_{1/2}$

is the half-life of the radioactive substance.

One curie is defined as $3.7\times {\text{ 10}}^{\text{10}}$

disintegration occurring per second.