RADIOACTIVE MATERIALS.

A power station makes electricity. Fossil fuel (coal, oil and gas) power stations and nuclear (uranium) power stations both use the same processes to make electricity. These are:

1. fuel produces heat and heat is used to boil water and is turned into steam
2. steam turns a turbine
3. turbine turns a generator and the generator makes electricity
4. electricity goes to the transformers to produce the correct voltage.

The only difference between fossil fuel and nuclear power stations is how the water is heated. Fossil fuel power stations burn their fuel while a nuclear power station uses the fission of uranium to generate heat.

Uranium is a non-renewable energy resource.

Nuclear reactors

As well as producing heat the nuclear reactor can be used to make other materials radioactive. The chain reaction inside the reactor releases neutrons. If a material is put into the reactor some of these neutrons may be absorbed by the nuclei of its atoms. This will make an atom's nucleus unstable which means it has become radioactive. These man-made radioisotopes are often then used as tracers in hospitals to diagnose and treat patients or in industry to detect leaks in pipes. The nuclear reactor is designed to allow a controlled chain reaction to take place.

nuclear bomb: the energy explodes.

NON-RENEWABLE- will eventually run out.

-fossil fuels (coal, oil and gas)

- nuclear power

RENEWABLE- will not run out

- tidal

-geothermal

-wind

-solar

NORMAL POWER STATIONS.

• fossil fuel is burned in a boiler.
• it becomes steam, and then the steam drives the turbine.
• the turbine turns the generator.
• the generator is connected to a transformer.
• it cools, and then is reused.

^^ NON RENEWABLE.

renewable sources of energy drive the turbine without burning fuels.

A SECONDARY ENERGY SOURCE IS MADE FROM PRIMARY ENERGY SOURCES.

PROTONS, NEUTRONS AND ELECTRONS.

(ELECTRONS- MASS IS NEARLY NOTHING.)

an isotope: an atom with a different number on neutrons, ( mass number)

PROTON- ATOMIC

ELECTRON- ATOMIC

NEUTRON- (MASS - ATOMIC)

ALPHA, BETA AND GAMMA.

radioactive- substances are unstable and give out radiation ( from nucleus)

the nucleus is more stable after emitting radiation (radioactive decay)

ALPHA, BETA AND GAMMA ARE IONISING. 

GAMMA IS WORSE (OUTSIDE BODY)

ALPHA IS WORSE (INSIDE BODY)

'background radiation'- food, radon gas, cosmic rays, gamma rays, medical.

'half life'- time taken for half of the radioisotopes to decay- they never reach 0.