Transmutation is a process in nuclear chemistry where one chemical element is transformed into another through changes in the atomic nucleus. This can occur naturally, as in radioactive decay, or artificially, through nuclear reactions.
Example: A classic example of transmutation is the conversion of uranium-238 (\(^{238}\text{U}\)) into plutonium-239 (\(^{239}\text{Pu}\)). This process occurs in nuclear reactors where uranium-238 absorbs a neutron to become uranium-239, which then undergoes two beta decays to ultimately produce plutonium-239. This illustrates how a nuclide can change its identity and properties through nuclear reactions.