Question

Help please

If you have 100 grams of a radioactive isotope with a half-life of 10 years:
part a: How much of the isotope will you have left after 10 years?
part b: How much of the isotope will you have left after 20 years?
part c: How many half-lives will occur in 40 years?

Answer 1

part a: How much of the isotope will you have left after 10 years?

• 100/2 = 50 g

part b: How much of the isotope will you have left after 20 years?

• 50/2 = 25 g

part c: How many half-lives will occur in 40 years?

• 40/10 = 4