Question

What is the purpose of Boron rods in a nuclear reactor?
A) Absorb the excess neutrons
B) Absorb alpha particles
C) Slow down the speed of neutrons
D) Speed up the reaction

Answer 1

Hint:In a nuclear reactor multiple fission chain reactions take place which releases numerous neutrons, in order to limit these neutrons boron rods are used.
Boron rods and sometimes heavy water is also used to limit the neutrons being generated. We define the nuclear reactor first and then proceed for the problem further.

Complete answer:
Let’s define an elaborate nuclear reactor.
A nuclear reactor is a device used to initiate and control a self-sustained nuclear chain reaction. Nuclear reactors are used at nuclear power plants for generation of electricity and in nuclear marine propulsions.
Nuclear reactors convert the energy released by controlled nuclear fission reaction into thermal energy for further conversion to mechanical or electrical forms. When a large atomic nucleus such as uranium 235 absorbs neutrons it undergoes the process of fission. The heavy nucleus of the atoms splits into two or more lighter nuclei releasing kinetic energy, gamma radiation and free neutrons. The kinetic energy of fission products is converted to thermal energy when these nuclei collide with nearby atoms, thus causing a chain reaction.
To control such a nuclear chain reaction, control rods containing neutron poisons and neutron moderators which can limit the number of increasing neutrons that will cause further fission reactions in a nuclear reactor.
Thus, Boron rods are the control rods which absorb the neutrons to limit their reaction.

Hence, Option A is correct.

Note: Nuclear reactors are used in thermal power stations for producing electricity; some reactors are used to produce isotopes for medical and industrial use or for production of weapons-grade plutonium. Steam generated in the nuclear reactor can be used for industrial process heat.