Given below are two statements:

Statement I: In a breeder reactor more fissile material is produced than it is consumed.

Statement II: In a breeder reactor, breeding works best with slow neutrons and hence moderators are required.

In light of the above statements, choose the most appropriate answer from the options given below:

The correct answer is Statement I is correct but Statement II is incorrect.
Key PointsStatement I: In a breeder reactor more fissile material is produced than it is consumed.

• A breeder reactor is a type of nuclear reactor in which more fissile material is produced than consumed.
• This is achieved by using fertile material such as uranium-238 as fuel and converting it into fissile material such as plutonium-239.
• The process of converting fertile material into fissile material is known as breeding, and hence the reactor is called a breeder reactor.
• The excess fissile material produced can be used as fuel in other nuclear reactors or in the production of nuclear weapons.

Therefore, Statement I is  correct.

Statement II: In a breeder reactor, breeding works best with slow neutrons and hence moderators are required.

• Statement II is not correct
• In a breeder reactor, breeding works best with slow neutrons, which have a higher probability of being captured by the fertile material and converted to fissile material.
• In a breeder reactor, breeding actually works best with fast neutrons, not slow ones.
• Therefore, moderators (which slow down neutrons) are generally not used in breeder reactors. Instead, breeder reactors often use a fast-neutron spectrum to facilitate the conversion (breeding) of fertile material into fissile material.