Radioactive Decay: How Unstable Nuclei Transform

Radioactive decay happens when unstable nuclei release energy to become stable.
Alpha decay emits two protons and two neutrons—essentially a helium nucleus.
Beta decay changes a neutron into a proton, or vice versa, by emitting an electron or positron.
Gamma decay releases high-energy photons without changing the number of protons or neutrons.
Each decay type lowers the nucleus’s energy, moving it toward stability.
Radioactive half-life measures how long it takes half a sample to decay.
Some isotopes decay in fractions of a second, while others last billions of years.
Radioactive decay fuels Earth’s heat and helps date ancient rocks and fossils.
Nuclear medicine uses controlled decay for imaging and targeted cancer treatments.
The weak nuclear force drives many decay processes, reshaping matter itself.