Question

The half-life of a radioactive isotope is the time it takes for a quantity of the isotope to be reduced to half its initial mass. Starting with 155 grams of a radioactive isotope, how much will be left after 5 half-lives?

Use the calculator provided and round your answer to the nearest gram.

Answer 1

After 5 half-lives, the remaining mass of the radioactive isotope will be 155 * (1/2)^5 = 4.84375 grams. Rounded to the nearest gram, the answer is 5 grams.

Explanation: