Chapter 40, Problem 12A

To determine

The factor that controls the chain reaction in a nuclear reactor.

Explanation of Solution

Introduction:

The chain reaction is the reaction in which every neutron of fission reaction stimulates another one fission reaction. The high amount of energy generates in chain reaction due to uncontrolled nature of reaction.

The energy of the fission reaction uses in the nuclear to generate electricity. The nature of the fission reaction is uncontrolled. The neutrons produces in the fission reaction can initiate the chain reaction. So, it is necessary to control these neutrons to initiate further fission reaction.

The speed of the neutrons produced in the primary fission reaction reduces by the use of moderator. The graphite core works as the moderator in the nuclear reactor. The control rod also absorbs the neutrons of the primary fission reaction. The control rods are made of cadmium or other heavy elements. The energy releases from the fission reaction controlled by the use of coolant.

Conclusion:

Thus, the moderator, control rods and coolant controls the chain reaction in the nuclear reactor.