WHAT IS NUCLEAR FISSION

The disintegration of an atomic nucleus into two or more smaller fragments. Fission is a form of radioactivity and, like other forms, may be spontanious or induced by irraditiation. In fission, nuclei usually disintegrate to form two fragments of roughly comparable mass number along with several neutrons.For examble the neutron-induced fission of U ²³⁵  could yield Kr⁹⁰ and Ba¹⁴³

          ²³⁵U_{92 +}¹n_0→⁹⁰Kr₃₆ +¹⁴³Ba₅₆ = 3¹n₀ +energy