Radioactive Decay & Half-life Midterm Review

Front

What is radioactive decay?

Back

Radioactive decay is the process by which an unstable atomic nucleus loses energy by emitting radiation, resulting in the transformation of the element into a different element or isotope.

Front

What is an alpha particle?

Back

An alpha particle is a type of radiation consisting of two protons and two neutrons, which is emitted during alpha decay.

Front

What is a beta particle?

Back

A beta particle is a high-energy, high-speed electron or positron emitted during beta decay.

Front

What is gamma radiation?

Back

Gamma radiation is a form of electromagnetic radiation of high frequency and energy, emitted from a nucleus during radioactive decay.

Front

What is half-life?

Back

Half-life is the amount of time it takes for half the nuclei in a sample of a radioactive isotope to decay.

Front

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

Back

Remaining amount = Initial amount × (1/2)^(number of half-lives).

Front

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

Back

12.5 g remains after 30 years.

Front

What happens to the atomic number of an element during alpha decay?

Back

The atomic number decreases by 2 during alpha decay.

Front

What happens to the atomic number of an element during beta decay?

Back

The atomic number increases by 1 during beta decay.

Front

What is the decay series?

Back

A decay series is a sequence of radioactive decay processes that an unstable isotope undergoes until it reaches a stable isotope.