Q: 32 (IAS/2011)
question_subject:
Science
question_exam:
IAS
stats:
0,87,57,87,19,35,3
keywords:
{'nuclear reactor': [0, 1, 1, 1], 'reactor': [0, 0, 1, 1], 'nucleus reaction': [0, 0, 0, 1], 'heavy water': [0, 0, 0, 3], 'neutrons': [0, 0, 1, 1], 'function': [11, 2, 3, 13]}
The function of heavy water in a nuclear reactor is to slow down the speed of neutrons.
In a nuclear reactor, the neutrons released from fission reactions need to be slowed down or moderated so that they can effectively trigger further fission reactions. Heavy water, which contains a higher concentration of deuterium (an isotope of hydrogen with an additional neutron in its nucleus), is an effective moderator because its increased mass slows down neutrons more effectively than ordinary water. This allows the neutrons to trigger further fission reactions and sustain the nuclear chain reaction.