Absolute Dating Review

Front

What is absolute dating?

Back

A method used to determine the actual age of a rock or fossil, often using radioactive decay.

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 12.5% of its original radioactive atoms left, how many half-lives have passed?

Back

3 half-lives.

Front

How do you calculate the age of a rock using half-lives?

Back

Multiply the number of half-lives by the length of one half-life.

Front

What is the half-life of Carbon-14?

Back

About 5,700 years.

Front

What is the half-life of Uranium-238?

Back

About 4.5 billion years.

Front

What is the significance of parent and daughter isotopes in radioactive dating?

Back

Parent isotopes decay into daughter isotopes over time, allowing scientists to determine the age of a sample.

Front

How much of the parent isotope remains after 2 half-lives?

Back

25%.

Front

What method would you use to date animal bones?

Back

Carbon dating.

Front

If a rock has 16 parent isotopes and 16 daughter isotopes, how many half-lives have occurred?

Back

1 half-life.