Nuclear Fission
Nuclear fission is a process in which a heavy nucleus—usually one with a nucleon number of two hundred or more—separates into two nuclei. Usually the division liberates neutrons and electromagnetic radiation and releases a substantial amount of energy. The discovery of nuclear fission is credited to Otto Hahn and Fritz Strassman. In the process of bombarding uranium with neutrons in the late 1930s, they detected several nuclear products of significantly smaller mass than uranium, one of which was identified as 137Ba. The theorectical underpinnings that exist to this day for nuclear fission were proposed by Lise Meitner and Otto Frisch. Shortly after Hahn and Strassman's discovery.
Some heavy nuclei will fission spontaneously. Others can be induced to fission through interaction with a neutron. In both spontaneous nuclear fission and induced nuclear fission the pool of neutrons and protons is conserved. For example, the nucleus 252Cf (Californium) fissions spontaneously. The 98 protons and 154 neutrons in the nucleus of 252Cf are reconfigured into other nuclei. Usually a few neutrons are released in the process. Pictorially, a typical spontaneous fission of 252Cf producing two nuclei and three neutrons is shown in Figure 1.
The pictorial depiction of the spontaneous fission of 252Cf can be summarized as an equation:The nucleus 235U (uranium) does not fission spontaneously, but it can be induced to fission through interaction with a neutron.
This is a free page. This page contains 201 words. This
article contains 3,822 words (approx. 13 pages at 300
words per page).
Read the rest of this Article with our Nuclear Fission Access Pass.