Nuclear Fission

• nuclear fission is the splitting of a large and unstable nucleus
• spontaneous fission is usually rare. usually, for fission to occur the unstable nucleus must first absorb a neutron
• the nucleus undergoing fission splits into two smaller nuclei, roughly equal in size, and emits two to or three neutrons plus gamma rays.
• energy is released by fission reaction
• all of the fission products have kinetic energy
• the neutrons may go on to start a chain reaction
• the chain reaction is controlled in a nuclear reactor to control the energy released. the explosion caused by a nuclear weapon is caused by an uncontrolled chain reaction