PPSC Chemistry Lecturer Preparation (Test # 04)- Malik Xufyan 03137355727

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PPSC CHEMISTRY CLASS
Test Session
CH: Nuclear Chemistry
Test # 04
For more WhatsApp # 0313-7355727
Topics:
1. Artificial radioactivity
2. Uses of radioisotopes
3. Nuclear reactors
4. Numerical problems
Artificial radioactivity
1. Artificial radioactivity was first discovered by
a) Seaberg
b) Rutherford
c) Einstein
d) Irene Curie &Juliot
2. Artificial transmutation was discovered by
a) Pauli
b) Rutherford
c) Soddy
d) Curie
3. Radioactive isotopes can be produced by the bombardment of _________ on stable
isotopes.
a) Protones
b) ɑ-particles
c) Neutrons
d) All of these
4. Artificial radioactive isotopes find major application in________________?
a) power generation
b) nuclear fission
c) nuclear fusion

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d) medical field
5. In the production of radioactive isotopes by bombardment with neutrons, which type
of neutrons are most effective?
a) Fast neutrons
b) Slow neutrons
c) Moderate neutrons
d) None
6. Which statement is true for all three types of radioactive emission?
a) They are deflected by electric fields
b) They ionise gases
c) They are completely absorbed by a thin aluminium sheet
d) They emit light
7. The number of protons or atomic number is reduced to 2 by which form of radioac-
tive decay?
a) Beta-decay
b) Gamma decay
c) Alpha decay
d) None of the above
8. Irene and Frederic Joliot Curie produced artificial radioactivity by nuclear reactions
in:
a) 1931
b) 1934
c) 1937
d) 1940
9. The elements whose atomic number is greater than 82 are naturally
a) unstable nuclei
b) stable nuclei
c) positive nuclei
d) negative nuclei
10. The artificially produced radioactive elements are known as
a) ions
b) radiant

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c) radioisotopes
d) transmutations
11. When a target nucleus is bombarded by an appropriate beam of particles, it is
possible to produce
a)a less massive nucleus, but not a more massive one.
b)a more massive nucleus, but not a less massive one.
c)a nucleus with smaller atomic number, but not one with a greater
atomic number.
d)a nucleus with greater atomic number, but not one with a smaller atomic number.
e)a nucleus with either greater or smaller atomic number.
12. Which of the following statements about radioactivity of an elementis incorrect
a) It is a nuclear property
b) It does not involve any rearrangement of electrons
c) Its rate is affected by change in temperature and/or pressure
d) It remains unaffected by the presence of other element orelements chemically combined
with it
13. The first artificial disintegration of an atomic nucleus was achievedby
a) Geiger
b) Wilson
c) Madame curie
d) Rutherford
e) Soddy
Uses of radioisotopes
14. The chief hazard of radiation is
a) damage to living cells due to ionization.
b) damage to cells due to heating.
c) damage to living cells due to the creation of chemical impurities.
d) the creation of new isotopes within the body.
15. Neutron is used as a
a) Reducing agent
b) Moderator
c) Tracer

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d) In biological programme
16. Which of the following radioisotope is used in luminous signs
a) Phosphorus- 32
b) Tritium
c) Sodium- 24
d)Radiocobalt
17. Co-60 is used in cancer treatment which is a ______ source
a) Alpha
b) Beta
c) Gamma
d) Delta
18. Which isotope is used in the study of functioning of vitamin B12 in the body?
a) Co-60
b) Co-67
c) Co-58
d) All of above
19. Which of the following is an alpha-emitter and used in smoke detector?
a) Na-24
b) Co-57
c) C-14
d)Am-241
20. Fe-59 is used in
a) Detection of anaemia
b) Age of material
c) Radiotherapy
d) locate brain tumors
21. C-14 is used in
a) Radiocarbon dating
b) To study the process of photosynthesis
c) In the investigation of respiration by plants
d) All of these
22. I-131 is beneficial in medical field due to its use in
a) Study the functioning of thyroid
b)Treat Grave’s disease

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c) Locating brain tumers
d) All of above
23. Radon is a _______ source and used in the treatment of non-healing wounds.
a) Alpha
b) Beta
c) Gamma
d) Delta
24. Which of the following is used in lung imaging in lung cancer
a) Am-124
b) Na-24
c) Xe-133
d) Fe-55
25. To trace the path of phosphorus, the isotope of phosphorus which is added to the
fertilizers, is
a) Phosphorus-31
b) Phosphorus-32
c) Phosphorus-33
d) Phosphorus-34
26. Which of the following is radioactive?
a) hydrogensulfide
b) vimentin
c) tritium
d) deuterium
27. Which radioisotope has powered more than 20 NASA spacecraft since 1972.
a) P-32
b) Pu-238
c) Co-59
d) Se-75
28. Which one is used to study bone formation and metabolism.
a) Strontium-85
b) Sulphur-35
c) Radium-226
d) Polonium-210

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29. Which of the following is used as fuel in nuclear power plant?
a) U-235
b) Pu-239
c) Xe-133
d) Both a & b
30. Which radioisotopes of Iodine are helpful in medical field?
a) I-123
b) I-125
c) I-129
d) I-131
e) All of above
31. Which of the following is used to study cellular functions and bone formation in
mammals.
a) Ca-47
b) S-35
c) C-14
d) Cr-51
32. Radioactive carbon dating was discovered by
a) G.N. Lewis
b) W.F. Libby
c) J. Willard Gibbs
d) W. Nernst
Nuclear Reactors
33. Nuclear reactor is based on the principle of
a) Controlled nuclear fission
b)Controlled nuclear fusion
c) Fusion reaction
d) None of these
34. Fuel rods used in nuclear reactor are made of
a) Carbon
b)U-235
c) Pu-239
d) Both b & c
35. Purpose of moderator in nuclear reactor is

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a) Fasten the emitted neutrons
b) Slow down the emitted neutrons
c) Moderate speed of neutrons
d) All
36. Which of the following is used as moderator in nuclear reactor
a) Graphite
b) Heavy water
c) Both a & b
d) None
37. Control rods are usually made up of
a) Cd
b) U
c) Pu
d) S
38. Purpose of control rods is
a) to absorb slow neutrons
b)to absorb fast neutrons
c) providing fuel
d) None of above
39. Which of the following is used as coolant in nuclear reactor?
a) Ammonia
b) Water
c) Low melting alloy of Na and K metals
d) Both b & c
40. At high temperatures, which material is the best choice to be used as coolant in a
nuclear reactor?
a) Heavy water
b) Molten Potassium
c) Water
d) Molten Carbon
41. An atom bomb is a ____________
a) Controlled fission reaction
b) Controlled fusion reaction

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c) Uncontrolled fission reaction
d) Uncontrolled fusion reaction
42. Canning in the nuclear reactor is a process of coating the fuel with a material that
does not contaminate the coolant, also eliminates the radiation hazards. Which material
is used for this?
a) Aluminium
b) Magnesium
c) Stainless steel
d) All of these.
43. The reason for providing the thermal shielding is to _________________.
a) Absorb the fast neutrons
b) Protect the operating personnel from exposure to radiations
c) Prevent the reactor wall from getting heated
d)All of the above
44. Following is the property of effective moderator.
a) It contain zero weight atoms
b) It contains heavy weight atoms
c) It contains light weight atoms
d) none of the above
45. The most common material used for shielding is
a) black carbon paper
b) lead or concrete
c) graphite or cadmium
d) thick sheets
46. The first nuclear power plant in the world was commissioned in
a) U.S.A.
b) U.S.S.R
c) England
d) None of the above
47. The avarage thermal efficiency of modern nuclear power plant is about
a) 30%
b) 60%
c) 40%
d) 80%

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Numerical Problems
47. How many milligrams of tritium will remain after 49.2 years if the starting amount
is 32 mg? The half-life of tritium is 12.3 years.
(a) 8 mg
(b) 2 mg
(c) 1 mg
(d) 4 mg
48. Find the half-life of 6
14
C if is 2.31 x 10-4
.
(a) 4 x 103
years
(b) 3 x 103
years
(c) 3.5 x 104
years
(d) 2 x 102
years
49. 200 mg of 14
C will become 25 mg in how many years if the half-life is 5760 years?
(a) 5760 years
(b) 17280 years
(c) 23040 years
(d) 11520 years
50. If a body requires 0.01 m activity of radioactive substance (half-life = 6 hrs) after 24
hrs of injection then what is the maximum activity of injection to be injected?
(a) 0.04
(b) 0.32
(c) 0.16
(d) 0.08

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51. What would be the remaining concentration of 300 g of radioactive substance after
18 hours if the half-life is 3 hours?
(a) 9.37 g
(b) 2.34 g
(c) 3.34 g
(d) 4.68 g
52. What would be the remaining concentration of 1 g of radioactive substance after 400
days if the half-life is 100 days?
(a) 1/16
(b) 1/4
(c) 1/2
(d) 1/8
53. What would be the remaining concentration of 10.4 micrograms of 231
Pa after 3.25 x
105
years if the half-life is 3.25 x 104
years?
(a) 0.0240 micrograms
(b) 2.18 micrograms
(c) 1.4 micrograms
(d) 0.0102 micrograms
54. The radioactive isotope of phosphorus, P-32 is used as a tracer in the liver. If 3.5 mg
is left in a sample after 288 hrs then how much P-32 was administered initially? [Half-
life of P-32 is 14.3 days]
(a) 7 mg
(b) 6.26 mg
(c) 1.96 mg
(d) 4.17 mg

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55. Uranium-238 forms thorium-234 after radioactive decay and has a half-life of 4.5 x
109
years. How many years will it take to decay 75% of the initial amount?
(a) 4.5 x 109
years
(b) 9 x 1010
years
(c) 4.5 x 1010
years
(d) 9 x 109
years
(d) neutron