Question

5. The half-life of radon-222 is 3.8 days. How much of a 100. kg sample is left after 15.2 days?(1 point)

Answer 1

* Half life is 3.8 days,

So, 15.2 days will have 4 half life (15.2/3.8).

So, the sample left after 15.2 days will be,

Therefore 6.25 kg of the sample left after 15.2 days.

$100\times\frac{1}{2}\times\frac{1}{2}\times\frac{1}{2}\times\frac{1}{2}=6.25\text{ kg}$