Half Life Decay

Front

What is radioactive decay?

Back

Radioactive decay is the process by which unstable atomic nuclei lose energy by emitting radiation, transforming into a different element or isotope.

Front

What is half-life?

Back

Half-life is the time required for half of the radioactive atoms in a sample to decay into another element or isotope.

Front

What is the half-life of iodine-131?

Back

The half-life of iodine-131 is 8 days.

Front

How many half-lives does it take for a radioactive sample to be considered completely decayed?

Back

A radioactive sample is considered completely decayed after 10 half-lives.

Front

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

Back

It will take 3 half-lives.

Front

How much of a 10 mg sample of iodine-131 is left after 24 days?

Back

1.25 mg is left after 24 days.

Front

What happens to the mass of a radioactive substance after each half-life?

Back

The mass of a radioactive substance is halved after each half-life.

Front

If a substance has a half-life of 5 years, how much of a 100 g sample remains after 15 years?

Back

After 15 years (3 half-lives), 12.5 g remains.

Front

What is an isotope?

Back

An isotope is a variant of a chemical element that has the same number of protons but a different number of neutrons.

Front

What is the significance of half-life in medicine?

Back

Half-life is significant in medicine for determining the dosage and timing of radioactive treatments.