Half-Life

Front

What is half-life?

Back

Half-life is the time required for half of the radioactive atoms in a sample to decay.

Front

If the half-life of a substance is 8 days, how much of a 10 mg sample remains after 24 days?

Back

1.25 mg

Front

What is a parent isotope?

Back

A parent isotope is the original radioactive isotope that undergoes decay to form a daughter isotope.

Front

What is a daughter isotope?

Back

A daughter isotope is the product of the decay of a parent isotope.

Front

How many half-lives are in 24 days if the half-life is 8 days?

Back

3 half-lives.

Front

If you start with 4.0 g of strontium-90, how much remains after 100 years if its half-life is 25 years?

Back

0.25 g

Front

What type of decay results in the emission of an alpha particle?

Back

Alpha decay.

Front

What is beta decay?

Back

Beta decay is a type of radioactive decay in which a beta particle (electron or positron) is emitted.

Front

How long does it take for a substance to decay from 100 to 50 if its half-life is 10 seconds?

Back

10 seconds.

Front

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

Back

The amount of the substance is reduced by half.