P2- energy from the nucleus

nuclear fission

• it is the splititng of an atomic nucleus
• there are two isotopes used in reactors uranium-235 and plutonium-239
• most reactors used enriched uranium because it contains 2-3% and is fissionable
• for fission to occur the nucleus must absorb the neutron, the nucleus then splits into two smaller nuclei and in this process 2-3 more neutrons are emitted and energy is released, these extra neutrons go on to form a chain reaction

nuclear fusion

• it is the process of forcing two nuclei close enough so they join to form a larger nucleus
• can happen by making two light nuclei collide at very high speed, this occurs in stars and huge amounts of energy are released
• nuclei of the same charge repel eachother so they must be heated to very high temperatures to overcome this
• because of this high temperature the reaction must occur in a magnetic field

nuclear issues

• major source of background radiation is radon gas which seeps through the ground from radioactive rocks
• it emits alpha particles so is a hazard if breathed in because alpha particles are ionising and cannot escape from the body
• cosmic rays from outer space and nuclear wepon testing at radiation to the atmosphere
• medical sources include xrays
• uranium and plutonium are chemically removed from the fuel rods and stored underground
• to reduce…