Fission and Chain Reaction in Nuclear
- On December 2, 1942 the first artificial nuclear chain reaction was produced by a team scientists led by Italian Physicist Enrico Fermi.
- When a slow neutron is bombarded on nucleus of 92235U, it is absorbed by the 92235U nucleus are 92235U compound nucleus is formed. Then nucleus splits into two elements of lower mass number namely Krypton and Barium. Also two or three neutrons at high speed are released and a lot heat energy is generated. Refer Figure B. These freed neutrons further strike another 92235U nucleus causing it to split and release of 2 or 3 neutrons and heat energy.
- The fission process or chain reaction can be stated with the following equation.
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| Figure A |
- The products of nuclear fission may change. There are no unique products of nuclear fission. Nearly 50 modes of fission reaction of 92235U are known . What particular fission reaction actually occurs is often a matter of chance.
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| Figure B |
- However in nuclear power plants this chain reaction is controlled by moderator and control rods. The moderator slows down the neutrons and control rods absorb the neutron. Thus, chain reaction can be controlled and desired heat energy can be obtained.
