Question

What is a decay series?

Short answer

A decay series, also known as a radioactive decay chain or decay sequence, is a series of radioactive isotopes that sequentially decay into one another until a stable, nonradioactive isotope is formed. The process involves the emission of radiation such as alpha particles, beta particles, or gamma rays, causing the nucleus to transform into a different element or isotope. The decay series continues through a sequence of steps, with each step representing a decay process, until a stable isotope is reached. One well-known example is the Uranium-238 decay series, which undergoes 14 radioactive decays to ultimately become stable Lead-206.

Step-by-step solution

Definition of Decay Series

A decay series, also called a radioactive decay chain or decay sequence, is a series of radioactive isotopes that decay into one another until a stable, nonradioactive isotope is formed.

Radioactive Decay

Radioactive decay is a process where an unstable atomic nucleus loses energy by emitting radiation, such as an alpha particle, beta particle, or gamma ray. This causes the nucleus to transform into a different element or a different isotope of the same element.

Decay Chain

In a decay series, the decay process continues as one radioactive isotope decays into another radioactive isotope, and so on. Each consecutive decay forms a step in the decay chain. This series of decay processes continues until a stable, nonradioactive isotope forms.

Example of a Decay Series

One well-known decay series is the Uranium-238 decay series. It consists of a sequence of 14 radioactive decays to ultimately become stable Lead-206: 1. Uranium-238 (U-238) decays to Thorium-234 (Th-234) through alpha decay. 2. Thorium-234 decays to Protactinium-234 (Pa-234) through beta decay. 3. Protactinium-234 decays to Uranium-234 (U-234) through beta decay. And so on, until it finally becomes stable Lead-206 (Pb-206). Remember, in a decay series, each step involves the emission of radiation (alpha particles, beta particles, or gamma rays) to transform into another isotope. This continues until a stable isotope is reached, ending the decay series.