What is radioactivity?

Radioactivity refers to the spontaneous decay of certain isotopes, a fundamental concept in nuclear physics. This process occurs when unstable atomic nuclei lose energy by emitting radiation, which can take the form of alpha particles, beta particles, or gamma rays. During this decay, the original unstable isotope transforms into a different element or a more stable isotope, often releasing energy in the process.

Understanding radioactivity is crucial as it has practical applications across various fields, including medicine, energy production, and geological dating. The concept is rooted in the properties of certain isotopes, which have an excess of energy or mass. This instability drives their transformation into more stable configurations through the emission of radiation, making it distinct from processes like nuclear fusion or light emission, which involve different physical phenomena.