Radioactive Decay

Radioactivity

An atom can have an unstable nucleus. An unstable nucleus can become more stable over time by randomly (spontaneously) emitting ionising radiation. This process is called radioactive decay.

**Radioactive substances: **Substances that decay radioactively are “radioactive substances”.

Decay is random: We cannot predict when an individual atom will emit (produce) ionising radiation.

An unstable nucleus can become more stable over time by randomly (spontaneously) emitting ionising radiation. This process is called radioactive decay. Substances that decay radioactively are “radioactive substances”.

Four Types of Ionising Radiation

Alpha radiation: Produced by alpha decay. Releases helium nuclei, also known as alpha particles.

Beta radiation: Produced by beta decay. Releases electrons, also known as beta particles.

Gamma radiation: Produced by gamma decay. It is a high-energy electromagnetic wave with a higher frequency than X-Rays.

Neutron radiation


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