Question

Energy is released in nuclear fission due to:
A. only a few mass is converted into energy
B. the total binding energy (B.E.) of fragments is more than the B.E. of parental element
C. total B.E. of fragments is less than the B.E. of parental element
D. total B.E. of fragments is equal to the B.E. of parental element

Answer 1

Hint: Nuclear fission is the process of splitting of two or more nuclei from a parent nucleus. The splitting of nuclei results in formation of smaller and lighter nuclei.

Complete answer:
Nuclear fission is a process in which a fast moving neutron collides with a heavy nucleus. This results in the formation of an unstable nucleus which undergoes degradation to form smaller nuclei with lower masses.
Apart from such types of nuclear fission induced by neutrons, in some cases self radioactive decay occurs naturally for unstable radioactive species. This is also referred to as nuclear fission which is spontaneous in nature.
The nuclear fission reaction enters into a chain reaction which goes on as neutrons are released after fission of the nucleus. The nucleus has two major forces present inside of which one is the attractive nuclear force between the nucleons and the other is the electrostatic force present between the protons.
For a successful fission reaction the energy required must overcome the attraction force which is also known as Binding energy. Hence energy released in nuclear fission is due to the total binding energy (B.E.) of fragments is more than the B.E. of parental element.
Thus option B is the correct answer.
The binding energy of fragments less than or equal to the parental element will not result in an exothermic reaction and thus no energy is released.

Note: The nuclear reaction is of four types like nuclear fission, nuclear fusion, nuclear decay and transmutation. The fragments which are produced have a combined mass which is less than the mass of the original parental compound. The difference in missing mass is equal to the nuclear energy released in the process.