P2 - Nuclear Radiation, its Uses, and its Dangers

• when unstable nucleus decays, it gives off nuclear radiation
• radioactive materials give off nuclear radiation over time
• 3 kinds of radiation: alpha, beta, gamma
• cause ionisation, which means atoms lose or gain electrons and turn them into ions
• when losing electrons, it becomes positive ion
• when gaining electron, becomes negative ion
• ionisation can cause reactions between atoms
• in human cells, ionisation can cause cancer
• high doses of radiation can kill cells
• depends on how far it can penetrate as to how much damage is made
• further the penetration before hitting atoms, the less ionisation caused

Alpha particles;

• big, heavy, slow moving
• 2 protons, 2 neutrons
• don't penetrate very far into materials
• strongly ionising

Beta particles;

• just electrons
• small, fast moving
• penetrate moderately, so moderately ionising

Gamma rays;

• type of EM radiation
• no mass, no charge, but high frequency
• penetrate long way into material, so weakly ionising

Alpha radiation used in;

• smoke detectors.

Beta radiation used in;

• tracers (medically)
• thickness control for paper.

Gamma radiation used;

• to treat cancer
• to sterilise medical equipment
• to test non-destructively.

• nuclear power stations use nuclear fission (where atoms in fuel are split in two to release heat energy)
• heat is then taken away by water, and the steam turns the turbines that run the generator.
• advantages of nuclear power;
  • lots of energy
  • little carbon dioxide production
  • takes much less uranium to produce the power
  • nuclear fuel reasonably cheap
  • lots of uranium in ground
• disadvantages of nuclear power;
  • expensive to build power stations
  • takes longer to set up a station for nuclear power than for fossil fuels
  • causes pollution to process
  • risk of leaks or catastrophe
  • radioactive waste is dangerous and difficult to dispose of
  • expensive to decommision power stations
  • non-renewable

• radioactive material requires safe storage
• short exposure times advised
• never use skin contact
• full protective suits
• lead lined suits, lead barriers, lead screens, etc
• remote controlled robot arms to carry out tasks
• radioactive waste remains for thousands of years
• could be used by terrorists
• could get into drinking water