Isotopes are atoms of an elements that have the same proton number(Z) but a different nucleon number(A)

Unstable isotopes which decay and give out radioactive emissions

Naturally occurring or artificially produced

Emits radioactive radiation which Have different penetrating ability with materials of

different thickness and densities Kill cells Cause cell mutation Ionise molecules

Have the same chemical properties as non-radioactive isotopes of the same element

Its activity decreases with time

Beryllium-7 is produced when boron-10 capturesa proton

Magnesium-24 is bombarded by a neutron, sodium-24 can be produced

MedicineAgricultureArchaeologyIndustries

Uses radiation to provide information about the function of the specific organs of a patient or to treat disease

A radioisotope is taken in by a patient The radiation emitted enables organs to be easily

imaged by imaging equipment Disorders can then be detected and treated

•Tracers Thyroid gland Iodine-131 will be used 1/4 of the total amount of iodine in the body can be

stored in the thyroid gland Amount of iodine entering the gland can be seen by

detecting the radioactive emitted from the radioactive iodine

γ or β emitter with a short half-life is used.

Thrombosis Sodium-24 is injected into the bloodstream to detect

the position of blood clots or thrombosis in the blood vessels

Brain tumour Can be detected and treated by using phosphorus-32

Sterilisation Radioisotope cobalt-60 is used to sterelise medical

equipments

Study the effectiveness of fertilisers Nitrogen-15 or phosphorus-32 is added to soil

water After the plant absorbed the soil water, the radioisotopes

can track uptake of fertiliser from root to leaves

Radioisotopes are used to kill pests and parasitesand to control the ripening of fruits

Induced genetic mutation in a plant Better strain Higher resistance against diseases

Carbon-14 is a radioisotope with a half-life of 5730 years and decays by emitting beta particles

Living animals and plants have a known proportion of carbon-14 in their tissues which remains constant and decreases when they die

The amount of carbon-14 left in a decayed plant or animal can be used to tell its age

K

The α - particles from polonium-210 is used to neutralize static charge in photographic plates and other materials

Water can be made radioactive by dissolving some radioactive salt which contains sodium-24

The β – particles emitted are detected by a GM tube

γ - rays can be used to penetrate deep into weldings to detect faults

•Tracers Underground pipe leaks Tracer will be added to the

liquid in the pipe Detector is moved along the

pipe The count rate will increase

as there is large amount of water

The radioactive source will be a short half-life γ emitter

K

•Thickness control The manufacture of aluminium

foil β emitter is placed above the

foil and a detector below it Some β particle will

penetrate the foil and the amount of radiation is monitored by the computer

The computer will send a signal to the roller to make the gap smaller or bigger based on the count rate