2. 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
3. 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
4. Beryllium-7 is produced when boron-10 captures
a proton
Magnesium-24 is bombarded by a neutron,
sodium-24 can be produced
6. 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
7. •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.
8. 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
9. 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 parasites
and to control the ripening of fruits
Induced genetic mutation in a plant
Better strain
Higher resistance against diseases
10. 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
11. 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
12. •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
13. •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
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