Question

Which element from following is used as moderator in nuclear reactor?

Options

• Mg

• Be

• Cs

• Ra

Answer 1

Be

Explanation:

Beryllium is used as a neutron moderator in some reactors because it efficiently slows fast neutrons by scattering while having a relatively low neutron-absorption cross‑section. A good moderator should be a light nucleus and absorb few neutrons; common moderators include hydrogen, deuterium, carbon and beryllium, which is used where its properties or compactness are advantageous.