Question

11. If 100. g of gold-198 decays to 12.5 g in 25.3 days, what is the half-life of gold-198?

Answer 1

Given data

*The amount of gold-198 is N = 100 g

*The gold-198 decays is n = 12.5 g

*The given time is T = 25.3 days

The expression for the radioactivity decay is given as

$N=n(\frac{1}{2})^{\frac{T}{t}}$

Substitute the values in the above expression as

$\begin{gathered} 100=12.5(\frac{1}{2})^{\frac{25.3}{t}} \\ t=8.43\text{ days} \end{gathered}$