What is 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.
What are the moderators used in nuclear reactor?
The commonly used moderators are water, heavy water (D2O) and graphite. This reduces the speed of fast neutrons and helps in sustaining nuclear chain reaction. Q. Common moderator used in nuclear reactor is ___ .
Which water is used as moderator in nuclear reactor?
Heavy water is used as a moderator in nuclear reactors.
Why heavy water is used as a moderator in thermal nuclear reactor?
In nuclear reactors, heavy water is generally used as a moderator because unlike normal water, which absorbs neutron, it slows down neutron without absorbing it.
Is water a neutron moderator or absorber?
Water and carbon (graphite) are commonly used moderators. Water is a good moderator, but the hydrogens in the water molecule have a fairly high cross section for neutron capture, removing neutrons from the fission process. Heavy water, used as moderator in Canadian reactors, avoids this loss.
When heavy water is used as a moderator then it is called?
Heary water ( D20 ) also called deuterium oxide, water composed of deuterium, the hydrogen isotope with a mass double that of ordinary hydrogen and oxygen. The heary water is used as a moderator of neutrons and also as a coolent in nuclear power plants.
What is the function of heavy water in a nuclear reactor Mcq?
Heavy water is used in nuclear reactors because it acts as a moderator in slowing down the neutrons that are produced during the fission reaction. This further helps in sustaining the chain reaction allowing the nuclear reactor to operate efficiently and with stability.
What does heavy water do in a nuclear reactor?
Nuclear power plants harness the energy of countless atoms of uranium splitting apart, or fissioning, in a chain reaction. Heavy water can help keep such a chain reaction going. As each uranium atom breaks apart, it shoots out neutrons that can go on to split other atoms.
Why is heavy water used as a moderator in a nuclear reactor Class 12?
It is used as a moderator in some nuclear reactors because it slows down neutrons easily and effectively also and has a low chance of absorption of neutrons.
What is the role of heavy water in nuclear reactor?
Heavy water is used in certain types of nuclear reactors, where it acts as a neutron moderator to slow down neutrons so that they are more likely to react with the fissile uranium-235 than with uranium-238, which captures neutrons without fissioning. The CANDU reactor uses this design.
Does heavy water absorb neutrons?
Heavy water is water for which the hydrogen isotope has a proton and a neutron, instead of just a proton, making it denser. … They absorb the neutrons and it transmutes the uranium into plutonium-239, so you’re creating plutonium by doing that. That’s what you’re doing in your reactor.
Which isotope is used as moderator in nuclear reactors?
B5 isotope is used as moderator in nuclear reactors.