Chapter 20, Problem 28E

Interpretation Introduction

Interpretation:

The time taken by the mass of a sample of $\text{thorium-234}$ to decay from $\text{84}\text{.5}\text{mg}$ to $\text{20}\text{.9}\text{mg}$ is to be stated.

Concept Introduction:

Half-life is defined as the time required for the number of nuclides to reach half of the original value. The remaining mass of a sample is calculated by the formula shown below.

$\text{R}=\text{S}\times {\left(\text{1}/\text{2}\right)}^{\text{n}}$