Nuclear Power Engineering Mcqs for Chemical - Set 7

1)   Which of the following is a moderating material used in nuclear reactor ?

a. Graphite
b. Cadmium
c. Zircaloy (an alloy of zirconium and aluminium)
d. Stainless steel
Answer  Explanation 

ANSWER: Graphite

Explanation:
No explanation is available for this question!


2)   Nuclear reactors are provided with shield to guard against the emission of mainly _____________ rays?

a. X
b. α and β
c. Neutrons & gamma
d. Infrared
Answer  Explanation 

ANSWER: Neutrons & gamma

Explanation:
No explanation is available for this question!


3)   The amount of a radioisotope remaining undecayed after a time equal to four times its half life, will be _____________ percent?

a. 3.125
b. 6.25
c. 12.50
d. 25
Answer  Explanation 

ANSWER: 6.25

Explanation:
No explanation is available for this question!


4)   Out of the following, nucleus of _____________ atom contains the largest number of neutrons?

a. U-235
b. U-238
c. U-239
d. Pu-239
Answer  Explanation 

ANSWER: U-239

Explanation:
No explanation is available for this question!


5)   Molten sodium (as a coolant in fast breeder reactor) ?

a. Can’t attain high temperature at normal pressure
b. Is not at all corrosive, even at a higher temperature
c. Is highly radioactive at elevated temperatures and can cause explosion, when it comes in contact with air or water
d. None of these
Answer  Explanation 

ANSWER: Is highly radioactive at elevated temperatures and can cause explosion, when it comes in contact with air or water

Explanation:
No explanation is available for this question!


6)   Commercial power generation from fusion reactor is not yet possible, because___________________?

a. It is difficult to control nuclear fusion reaction
b. The fuel required (i.e., deuterium & tritium) is scarce
c. It is difficult to initiate fusion reaction
d. Quantity of fuel required for initiating fusion reaction is prohibitively high
Answer  Explanation 

ANSWER: It is difficult to control nuclear fusion reaction

Explanation:
No explanation is available for this question!


7)   Thermal shield is used in high powered nuclear reactors to__________________?

a. Protect the walls of the reactor from radiation damage
b. Absorb the fast neutrons
c. Slow down the secondary neutrons
d. Protect the fuel element from coming in contact with the coolant
Answer  Explanation 

ANSWER: Protect the walls of the reactor from radiation damage

Explanation:
No explanation is available for this question!


8)   A radioactive substance does not emit________________?

a. α-ray
b. Proton
c. Position
d. β-ray
Answer  Explanation 

ANSWER: Proton

Explanation:
No explanation is available for this question!


9)   The ratio of neutrons to protons of an element having a mass number and atomic number of 80 and 40 respectively is ___________________?

a. 1
b. 0.5
c. 2
d. 4
Answer  Explanation 

ANSWER: 1

Explanation:
No explanation is available for this question!


10)   Coolant used in a boiling water reactor is________________?

a. Hydrogen gas
b. Water
c. Steam
d. A mixture of water & steam
Answer  Explanation 

ANSWER: A mixture of water & steam

Explanation:
No explanation is available for this question!


11)   
The 92U238 emits an a-particle. The product is____________________?


a. 90U234
b. 90U238
c. 90U236
d. 92U236
Answer  Explanation 

ANSWER: 90U234

Explanation:
No explanation is available for this question!


12)   Percentage of the heavy water in ordinary water is around ____________________?

a. 0.015
b. 7.54
c. 0.71
d. 32.97
Answer  Explanation 

ANSWER: 0.015

Explanation:
No explanation is available for this question!


13)   Which is the most commonly used molten metal for cooling of nuclear reactors ?

a. Calcium
b. Sodium
c. Mercury
d. Zinc
Answer  Explanation 

ANSWER: Sodium

Explanation:
No explanation is available for this question!


14)   Energy produced in the nuclear fission is of the order of _____________ MeV?

a. 20
b. 200
c. 1000
d. 2000
Answer  Explanation 

ANSWER: 200

Explanation:
No explanation is available for this question!


15)   _____________ have the same mass number, but different nuclear charge ?

a. Isotopes
b. Isobars
c. Isotones
d. None of these
Answer  Explanation 

ANSWER: Isobars

Explanation:
No explanation is available for this question!


16)   The mass number of an element is equal to the number of _____________ in the nucleus?

a. Electrons
b. Neutrons
c. Protons
d. Neutrons plus protons (i.e., nucleons)
Answer  Explanation 

ANSWER: Neutrons plus protons (i.e., nucleons)

Explanation:
No explanation is available for this question!


17)   Radioactive decay is a _____________ change?

a. Chemical
b. Nuclear
c. Physical
d. None of these
Answer  Explanation 

ANSWER: Nuclear

Explanation:
No explanation is available for this question!


18)   The atomic number of an element is equal to the number of ______________ present in its atom?

a. Neutrons
b. Electrons
c. Protons
d. Either B. or C.
Answer  Explanation 

ANSWER: Either B. or C.

Explanation:
No explanation is available for this question!


19)   “Critical mass” is the minimum mass of nuclear fissile material required for the__________________?

a. Sustainment of chain reaction
b. Power generation on commercial scale
c. Economic power generation
d. None of these
Answer  Explanation 

ANSWER: Sustainment of chain reaction

Explanation:
No explanation is available for this question!


20)   The atomic mass of an element is fractional, because ______________________?

a. Of uncertainty principle
b. It may have isobars
c. It contains neutrons
d. It may have isotopes
Answer  Explanation 

ANSWER: It may have isotopes

Explanation:
No explanation is available for this question!