Question

If there were 10 grams of a radioactive isotope, how much of the sample would be left after 1 half-life? How much after 2 half-lives?

Answer 1

Step-by-step explanation:

After one half-life, half of the radioactive sample would decay. So, if there were 10 grams initially, after one half-life, there would be 5 grams left.

After two half-lives, half of the remaining 5 grams would decay, leaving 2.5 grams.