Discuss the process of nuclear fission and its properties.

Explanation

When uranium nucleus is bombarded with a neutron. It breaks up into two smaller nuclei of comparable masses with the release of energy.

The process of breaking up of the nucleus of a heavier atom into two smaller nuclei with the release of a large amount of energy is called nuclear fission.
The fission is accompanied by the release of neutrons. The energy that is released in the nuclear fission is of many orders of magnitude greater than the energy released in chemical reactions.
Uranium undergoes fission reaction in 90 different ways. The most common fission reactions of `""_(92)^(235)"U"` nuclei are shown here.
`""_(92)^(235)"U + ""_(0)^(1)"n"` to `""_(92)^(236)"U^(ast)"` to `.(56)^(141)"Ba" + ""_(36)^(92)"Kr" + 3_(0)^(1)n + Q`
`""_(92)^(235)"U"` + `""_(0)^(1)"n" to ""_(92)^(236)"U^(ast)" to .(54)^(140)"Xa" + ""_(38)^(94)"Sr" + 2_(0)^(1)n + Q`
Here Q is energy released during the decay of each uranium nuclei. When the slow neutron is aborbed by the uranium nuclei, the mass number increases by one and goes to an excited state `""_(92)^(236)"U^(ast)"`. But these excited state does not last longer than `10^(-12)s` and average. 2.5 neutrons are emitted.