# Thorium-234 has a half life of 24 days. If you started with a 100-g sample of thorium-234 how much would remain after 48 days?

May 12, 2017

The mass remaining is $= 25 g$
Initial mass is $= 100 g$
After $24$ days, the mass will be $= \frac{100}{2} = 50 g$
After $48$ days, the mass will be $= \frac{100}{4} = 25 g$