Question #6ecac

1 Answer
Sep 26, 2015

No, 3 Neutrons produced isn't a given in any nuclear fission process.

Explanation:

The number of neutrons produced depends on the fission products formed in the process of bombarding an Uranium-235 atom or any other atom, with a neutron.

For example this picture gives the products possible in fission of Uranium-235 and the number of neutrons produced:

enter image source here
Image from: http://physics.nayland.school.nz/VisualPhysics/NZ-physics%20HTML/17_NuclearEnergy/Chapter17a.html

The above is referred to as prompt neutron production, because the neutrons are produced within #10^-14# seconds,the other type is delayed neutron production, after #10^-14# seconds.

Delayed neutron production is when the fission products, which are neutron-rich undergo beta decay, losing an electron, but are still excited. Now these let off a photon (gamma decay) or in addition let off neutrons, if excited enough, in order to become stable.

The delayed neutron production is important because in that way the neutrons can be controlled (prompt neutron production can't be controlled, because they occur very fast) with nuclear reactor control rods which are made of Boron, Silver, Indium and Cadmium, as well as there being Heavy Water in the primary loop of the three loops in the Nuclear Power Plant. Both of these absorb the excess neutrons so that there isn't a nuclear meltdown (runaway chain reaction).

Picture showing the control rods and uranium rods in reactor vessel and Heavy Water in Primary Loop:
enter image source here
Image from: http://www.eskom.co.za/Whatweredoing/ElectricityGeneration/KoebergNuclearPowerStation/Pages/Operating_Method.aspx

NB: More neutrons equals faster rate of fission.

Hope I helped :)