uses of radioisotopes
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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
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
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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
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•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