Chapter 8 Review

Front

What is the definition of half-life in the context of radioactive decay?

Back

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

Front

How do you calculate the remaining amount of a substance after a certain number of half-lives?

Back

To calculate the remaining amount, use the formula: Remaining Amount = Initial Amount × (1/2)^(number of half-lives).

Front

What is the half-life of iodine-131?

Back

8 days.

Front

If the half-life of strontium-90 is 25 years, how much of a 4.0 g sample remains after 100 years?

Back

0.25 g.

Front

What are homologous structures?

Back

Homologous structures are features in different organisms that share a common ancestor but have different functions.

Front

What is the half-life of barium-122?

Back

2 minutes.

Front

How much barium-122 remains from an 80 g sample after 10 minutes?

Back

2.5 g.

Front

If you start with 16 parent isotopes and end with 16 daughter isotopes, how many half-lives have occurred?

Back

1 half-life.

Front

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

Back

Half-lives are used to determine the age of materials by measuring the remaining amount of radioactive isotopes.

Front

How does the concept of half-life apply to medical treatments using radioactive isotopes?

Back

Understanding half-lives helps determine the dosage and timing of treatments involving radioactive isotopes.