1. Radioactive Materials

2.  Elements that emit radiation all the time are called radioactive  Radioactive elements that are found in the world around us emit background radiation  Background radiation comes from rocks, food, outer space etc

3. Radioactive Materials  If you are contaminated then you are carrying a source of radiation on your person  Irradiation means to fire radioactive particles at food, medical instruments to sterilize them.  There are three types of radiation Alpha, Beta and Gamma

4. Radioactive Materials  Ionising radiation damages living cells  When ionising radiation strikes living cells these may be killed or may become cancerous  Ionized molecules react more quickly

5. Radioactive Materials  alpha radiation is most likely to cause damage  gamma radiation is least likely to cause damage  Alpha stopped by paper  Beta stopped by Aluminium  Gamma stopped by lead

6. Radioactive Materials  ionising radiation can be used to: treat cancer  sterilise surgical instruments  sterilise food  You need to explain why?

7. Radioactive Materials  recall that radiation dose in measured in sieverts is a measure of the damage done to your body  Apply the ALARA principle to radiation  Apply the precautionary principle to radiation  Suggest ways to reduce risk

8. Radioactive Materials  Explain the difference between perceived risk and actual risk  Account for the difference between perceived risk and actual risk  The rate of radioactive decay cannot be changed  The nucleus of the atom is unstable ( has too much energy ) so gives out particles

9. Radioactive Materials  Half life what does it mean?  Calculate the activity after a number of half lives  The activity of a radioactive source get less with age,

10. Radioactive Materials  Power stations  Fuel Uranium, process fission  Chain reaction controlled by Control Rods  Radioactive waste  Lots of energy from a small amount of Uranium  Learn how a nuclear bomb works

11. Radioactive Materials  Why produce electricity  Easy to transport around  Can be used in many different ways  It is a secondary source of energu  Renewable sources of energy geothermal wind power etc  Fossil fuel power stations produce CO 2

12. Radioactive Materials  Advantages and disadvantages of different types of power stations  Can things be made totally safe?