Which statement about beta-minus (β−\beta^-β−) decay is correct?
The mass number of the nucleus increases.
The nucleus changes to that of a different element.
The nucleus does not decay until after at least one half-life.
After two half-lives, the rate of beta-minus decay falls to zero.
120 exam-style questions on CIE IGCSE Physics 5.2.3a Radioactive decay. Each one has a worked solution and a mark scheme showing where the marks go.