Question

The half-life of plutonium-241 is 14.4 years. How much of the original 3.6 grams of this

Answer 1

$\textit{Amount for Exponential Decay using Half-Life} \\\\ A=P\left( \frac{1}{2} \right)^{\frac{t}{h}}\qquad \begin{cases} A=\textit{current amount}\\ P=\textit{initial amount}\dotfill &3.6\\ t=\textit{elapsed time}\dotfill &45\\ h=\textit{half-life}\dotfill &14.4 \end{cases} \\\\\\ A=3.6\left( \frac{1}{2} \right)^{\frac{45}{14.4}}\implies A=3.6\left( \frac{1}{2} \right)^{3.125}\implies A\approx 0.41265$