Radiometric Dating

Front

What is Radiometric Dating?

Back

A method used to date materials by comparing the abundance of a radioactive isotope to its decay products.

Front

What is a half-life?

Back

The time required for half of the radioactive atoms in a sample to decay.

Front

How is the half-life of a radioactive isotope determined?

Back

By measuring the rate of decay of the isotope over time.

Front

If a radioactive isotope has a half-life of 200 years, how much of a 50-gram sample remains after 400 years?

Back

12.5 grams (after 2 half-lives).

Front

What is Carbon-14 used for in radiometric dating?

Back

To date organic materials up to about 50,000 years old.

Front

What happens to the amount of a radioactive isotope over time?

Back

It decreases as the isotope decays into stable products.

Front

Why can radiometric dating be used for dating rocks and fossils?

Back

Because the decay rates of radioactive isotopes are constant and can be measured accurately.

Front

What percentage of a radioactive substance remains after 3 half-lives?

Back

12.5%.

Front

If a sample originally had 100 grams of a radioactive isotope, how much will remain after 1 half-life?

Back

50 grams.

Front

What is the significance of the term 'decay constant'?

Back

It is a value that represents the probability of decay of a radioactive isotope per unit time.