6. FUNDAMENTALS OF RADIOISOTOPES
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Isotopes that are not stable and
go through radioactive decay
are known as
RADIOISOTOPES.
Radioisotopes exist naturally.
Radioisotopes have a wide
range of applications including
medicine, agriculture,
archaeology and industry
Stable isotopes
radioisotopes
Carbon-12
Carbon-14
Sodium-23
Sodium-24
Colbalt-59
Colbalt-60
Lead-207
Lead-210
ïŒExample of radioisotopes and their
stable isotopes
7.
8. Field
Isotopes application.
Medicine
provide information about the function of the specific organs or treat
disease. Cobalt-16 use to kill cancer cell without surgery in patients.
Iodine-131 are injected into patients to detect malfunction of thyroid
glands.
Agriculture
Radioisotopes are also used to kill pests and parasites and to control the
ripening of fruits. The metabolism of phosphorus in plants can be studied
using phosphate fertilisers that contains phosphorus-32.
Archaeolog
y
The amount of carbon-14 left in a decayed plant or animal can be used
to tell its age. Carbon dating uses carbon-14 to c
Industries
Îł-rays can used to detect faults. Water can be made radioactive by
dissolving some radioactive salt contains sodium-24. ÎČ-particles emitted
are detected by a GM tube. α-particles from polonium-2l0 is used to
neutralise static charge in photographic plates.
10. QUESTION!
1. X and Y are two isotopes. Which of these statements about X and Y is correct?
I. X and Y have the same proton numbers.
II. X and Y have different numbers.
III. There are more neutrons in an atom of Y than in an atom of X.
A.
B.
C.
D.
I and II only
I and III only
II and III only
I,II and III
11. 2. In a nuclear reactor, the neutrons produced are slowed down by the...
A.
B.
C.
D.
Concrete shield
Control rods
Graphite moderator.
Fuel rods.
12. 3. Radioactive waste is harmful to human being because..
A.
B.
C.
D.
It can explode if not handled with the correct procedure.
It emits radiation with a long half-life
It remains very hot for a long peroid of time.
It can leak out of containers.
13. 4. Which of the following statements is true for all the three radioactive
emission, i.e alpha particles, beta particles and gamma rays?
A. All the three radioactive emissions are stopped by a thick layer of
aluminium.
B. All the three radioactive emissions are deflected by magnetic field.
C. All the three radioactive emissions are deflected by electric field.
D. All the three radioactive emissions are capable of ionising the air.
14. 5.Radioisotopes in agriculture....choose the correct answer.....
Answer
Radioisotopes
Use in agriculture
A
Cobalt-60
Kill cancer cells.
B
Phosphorus-32
To determine the metabolism of
phosphorus in plants
C
Carbon-14
To estimate age of fossils and artefacts.
D
Iodine-131
Study the uptake by the thyroid glands.
15. 6. Which of the particles is used to initiate the fission of a nucleus of
uranium-235
A.
B.
C.
D.
High energy electron
Slow moving neutron
Fast moving proton
Fast moving neutron