Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus or the reaction of a nucleus with another particle. The first humanmade nucleus was produced in Ernest Rutherford’s laboratory in 1919 by a transmutation reaction, the bombardment of one type of nuclei with other nuclei or with neutrons. Rutherford bombarded nitrogen atoms with high-speed α particles from a natural radioactive isotope of radium and observed protons resulting from the reaction:

147N + 42He ⟶ 178O + 11H714N + 24He ⟶ 817O + 11H

The 178O817O and 11H11H nuclei that produce are stable, so no further (nuclear) changes occur.

Particle accelerators devices used to produce transmutation reactions. These devices use magnetic and electric fields to increase the speeds of nuclear particles. In all accelerators, the particles move in a vacuum to avoid collisions with gas molecules. When neutrons require transmutation reactions, they usually obtained from radioactive decay reactions or various nuclear reactions occurring in nuclear reactors. The Chemistry in Everyday Life feature that follows discusses a famous particle accelerator that made worldwide news.