Radiometric Dating

Front

What is radiometric dating?

Back

A method used to date materials by comparing the abundance of radioactive isotopes and their decay products.

Front

Why is radiometric dating possible?

Back

Because the rates of decay of radioactive isotopes are constant.

Front

What does radioactive decay measure?

Back

Absolute time.

Front

What are isotopes?

Back

Atoms of the same element that have different numbers of neutrons.

Front

How do carbon-12 and carbon-14 differ?

Back

They differ by the number of neutrons, not protons.

Front

What is a half-life?

Back

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

Front

If a rock sample has 25% of its original radioactive atoms left, how many half-lives have passed?

Back

2 half-lives.

Front

If the half-life of a radioactive substance is 100 years, how old is a rock with two half-lives?

Back

200 years.

Front

What is the significance of half-lives in radiometric dating?

Back

They help determine the age of rocks and fossils by measuring the decay of isotopes.

Front

What is the difference between relative time and absolute time?

Back

Relative time places events in order without exact dates, while absolute time provides a specific age.