Question

Introduction of which rod in a nuclear reactor controls chain reaction?
A) Iron rods
B) Silicon rods
C) Cadmium rods
D) Platinum rods

Answer 1

This is a chemical element with atomic number 48. The element is soft, silvery-white metal is chemically similar to the two other stable metals in group 12 of the periodic table.

Complete step by step solution:
plutonium. These are capable of absorbing many neutrons without fissioning themselves. The structure of control rods is designed for the neutron spectrum of the nuclear reactor. Rods are composed of boron, silver, indium, and cadmium which can absorb excess neutrons.
We know that some of the nuclei have a strong affinity for slow neutrons and can absorb them very easily. This is especially true for cadmium, which has a higher probability of capturing a neutron than ${\text{Uranium - }}235$ to undergo fission. The establishment of cadmium control rods in the center of nuclear reactors halts the chain reaction. This is why cadmium control rods are introduced or eliminated to slow down or increase the chain reaction. This type of introduction which is mechanical and relatively slow is used to manage the reactor power or to stop it down completely.

Hence the correct option is (C).

Additional information:
Most nuclear reactors use water as a moderator, which can also act as a coolant, although some do use graphite rods and the other neutrons that were released by the collision would lead to a nuclear explosion if control rods did not absorb them.

Note:
Control rods are a crucial technology for maintaining the optimum state of fission reactions inside a nuclear reactor. They account for real-time control of the fission process, which is important for both keeping the fission chain reaction active and preventing it from accelerating out of control.