3709. The mass number of an element is equal to the number of __________ in the nucleus.
electrons
neutrons
protons
neutrons plus protons (i.e., nucleons)
✅ The correct answer is option D.
3716. The ratio of volume of an atom to that of its nucleus is
1012
10-Dec
10-Aug
108
✅ The correct answer is option A.
3720. Primary purpose of a __________ nuclear reactor is to supply a high neutron flux of the order of 1013 to 1014 neutrons/cm2 second.
research
power
breeder
homogeneous
✅ The correct answer is option A.
3725. Which of the following is the best nuclear fuel?
Np- 239
U-234
Pu-239
Th-236
✅ The correct answer is option C.
3729. Heat is generated in a nuclear reactor (thermal) by
combustion of a nuclear fuel e.g. uranium.
fusion of atoms of uranium.
absorption of neutrons in uranium atoms.
fission of U-235 by neutrons.
✅ The correct answer is option D.
3732. Fuel for a fast breeder reactor is
plutonium
uranium
radium
neptunium
✅ The correct answer is option A.
3737. If 4 gm of a radioisotope has a half life period of 10 days, the half life of 2 gm of the same istotope will be __________ days.
5
10
20
30
✅ The correct answer is option B.
3742. How many atoms are present in one gm-atom of an element ?
2 x 1023
6 x 1023
6 x 1032
5 x 105
✅ The correct answer is option B.
3712. Atoms of U-238 and U-235 differ in structure by three
electrons and three protons
protons
neutrons
electrons
✅ The correct answer is option C.