Question

If the mass of a radioactive substance is 8 grams and it has half life of 4 hours, how much mass remains after 8 hours?

Answer 1

2 grams

Explanation:

The sample will lose half of its mass after 4 hours. The half life.

`8/2 = 4`

The sample will lose half of the remaining four after another half life.

`4/2 = 2`