Answer
The hydrogen nuclei of water can capture neutrons to form deuterium and thus remove neutrons from the chain reaction. This way it helps keep the chain reaction from multiplying in addition to serving as a neutron moderator.
Work Step by Step
The hydrogen nuclei of water can capture neutrons to form deuterium and thus remove neutrons from the chain reaction. This way it helps keep the chain reaction from multiplying in addition to serving as a neutron moderator.