Question

What is radioactivity?

Options

• The absorption of high-energy radiation by the nucleus of a stable atom

• The spontaneous emission of high-energy radiation from the nucleus of an unstable atom

• The emission of visible light from an atom when it is heated to a high temperature

• The release of energy during a chemical reaction between two stable compounds

Answer 1

Radioactivity is defined as the spontaneous emission of high-energy radiation from the nucleus of an unstable atom. It originates in the nucleus, not from electron transitions or chemical reactions, and occurs on its own without external influence.