The function of heavy water in a nuclear reactor is to
[UPSC Civil Services Exam – 2011 Prelims]
(a) Slow down the speed of neutrons
(b) Increase the speed of neutrons
(c) Cool down the reactor
(d) Both (a) and (c)
Answer: (a)
Explanation:
- Heavy Water – Heavy Water (D2O) or deuterium oxide is made up of two atoms of deuterium and one atom of oxygen.
- Use of Heavy Water – Heavy Water displays similar physical and chemical properties but differs in nuclear properties when compared to ordinary water which makes it an extremely efficient material for use as moderator and coolant in Pressurized Heavy Water Reactor (PHWRs).
- Moderator – Moderator is required in a Nuclear reactor to slow down the neutrons produced during the fission reaction so that the chain reaction can be sustained. Heavy Water is an excellent moderator due to its high moderating ratio and low absorption cross-section for neutrons.
