Half Life

You have 100 grams of radioactive C-14. The half life of C-14 is 5730 years.

How many grams are left after 1 half life?

Imagine you have 50,000 atoms of uranium-238. If U-238 has a half-life of 4.5 billion years, how many U-238 atoms will be left after 4.5 billion years?

If 10 mg of iodine 131 is given to a patient, how much is left after 24 days? The half-life of iodine-131 is 8 days.

After the third half-life, how much of the sample is left?

What percent of carbon-14 would be left after 5730 years?

What is the half-life of iodine-131?

The time it takes for a radioactivity level to drop by a half is is the sample's ___________________.

If the half-life of uranium-232 is 70 years, how many half-lives will it take for 10 g of it to be reduced to 1.25 g?