What is radioactive decay and how does it occur?

Radioactive decay is the process where unstable atomic nuclei lose energy by emitting radiation.

Radioactive decay is a spontaneous process that occurs in certain elements, such as uranium, radon, and radium, which have unstable atomic nuclei. These elements are known as radioactive isotopes. The instability is due to an imbalance in the number of protons and neutrons in the nucleus. To regain stability, these nuclei undergo radioactive decay, which involves the emission of radiation in the form of alpha particles, beta particles, or gamma rays.

Alpha decay occurs when the nucleus emits an alpha particle, which consists of two protons and two neutrons. This results in the formation of a new element that is two places lower in the periodic table. Beta decay, on the other hand, involves the transformation of a neutron into a proton and an electron. The electron, known as a beta particle, is then emitted from the nucleus. The new element formed is one place higher in the periodic table. Gamma decay does not result in the formation of a new element but involves the emission of high-energy photons, known as gamma rays, to lower the energy state of the nucleus.

The rate at which radioactive decay occurs is measured in terms of half-life, which is the time taken for half of the radioactive isotopes in a sample to decay. This is a constant value for each radioactive isotope and is not affected by external factors such as temperature or pressure.

Understanding radioactive decay is crucial in various fields, including nuclear power generation, medical imaging, and archaeological dating. It's also important for understanding the dangers and precautions needed when handling radioactive materials.