2nd Quarter Bonus

Front

What is the term for the time it takes for 50% of the nuclei in a radioactive sample to decay?

Back

The half-life.

Front

If a material has 12.5% of the original radioactive atoms remaining and the half-life is 60 years, how old is the material?

Back

180 years old.

Front

What is the half-life of carbon-14?

Back

5,730 years.

Front

What is the concept that explains how layers of a planet are sorted by density during its formation?

Back

Planetary differentiation.

Front

Who developed the theory of continental drift?

Back

Alfred Wegener.

Front

Define half-life in the context of radioactive decay.

Back

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

Front

What percentage of the original radioactive material remains after two half-lives?

Back

25%.

Front

If a radioactive substance has a half-life of 10 years, how much of a 100g sample remains after 30 years?

Back

12.5g.

Front

What is the relationship between half-life and the stability of a radioactive isotope?

Back

A shorter half-life indicates a less stable isotope.

Front

Explain the process of radioactive decay.

Back

Radioactive decay is the process by which an unstable atomic nucleus loses energy by emitting radiation.