What is the radius of iodine atom? (atomic No.53, Mass No.126)
2.5 × 10-11 m
2.5 × 10-9 m
7 × 10-9 m
7 × 10-6 m
Curie is a unit of
energy of gamma rays
half - life
radioactivity
intensity of gamma rays
In the nucleus of 11Na23, the number of protons, neutrons and electrons are
11, 12, 0
23, 12, 11
12, 11, 0
23, 11, 12
The nucleus 48Cd115, after two successive β-decay will give
46Pa115
49In114
<p><sub>50</sub>Sn<sup>113</sup></p>
<p><sub>50</sub>Sn<sup>115</sup></p>
The nuclei 6C13 and 7N14 can be described as
Isotones
Isobars
isotopes of carbon
isotopes of nitrogen
Which of the following statements is true for nuclear forces?
They obey the inverse square law of distance.
They obey the inverse third power law of distance.
They are short range forces.
They are equal in strength to electromagnetic forces.
The mass density of a nucleus varies with mass number A as
A2
A
Constant
1/A
Heavy water is used as a moderator in a nuclear reactor. The function of the moderator is
To control energy released in the reactor
To absorb neutrons and stop chain reaction
To cool the reactor
To slow down the neutrons to thermal energies
The ratio of the radii of the nuclei 13Al27 and 52Te125 is approximately
6 :10
13 : 52
40 : 177
14 : 73
The energy equivalent of one atomic mass unit is:
1.6 × 10-19 J
6.02 × 1023J
931 MeV
9.31 MeV
