Half-lives and the random nature of radioactive decay

Radioactive decay is random.

The half-life of a radioactive isotope is the time it takes for the number of nuclei of the isotope in a sample to halve, or the time it takes for the count rate (or activity) from a sample containing the isotope to fall to half its initial level.

Students should be able to explain the concept of half-life and how it is related to the random nature of radioactive decay.

WS 1.2

Students should be able to determine the half-life of a radioactive isotope from given information.

MS 4a

(HT only) Students should be able to calculate the net decline, expressed as a ratio, in a radioactive emission after a given number of half-lives.