know that nuclear reactions, including fission, fusion and radioactive decay, can be a source of energy

understand how a nucleus of U-235 can be split (the process of fission) by collision with a neutron, and that this process releases energy as kinetic energy of the fission products

know that the fission of U-235 produces two radioactive daughter nuclei and a small number of neutrons

describe how a chain reaction can be set up if the neutrons produced by one fission strike other U-235 nuclei

describe the role played by the control rods and moderator in the fission process

understand the role of shielding around a nuclear reactor

explain the difference between nuclear fusion and nuclear fission

describe nuclear fusion as the creation of larger nuclei resulting in a loss of mass from smaller nuclei, accompanied by a release of energy

know that fusion is the energy source for stars

explain why nuclear fusion does not happen at low temperatures and pressures, due to electrostatic repulsion of protons