Environmental Engineering Reference
When ission of a uranium-235 atom takes place, the nucleus of the atom is split apart. This
results in the release of two or three neutrons, lighter elements, and a great deal of energy.
Certain uranium and plutonium atoms are particularly suitable
for making electricity. Their nuclei can split apart if they
happen to be “hit” by a neutron. This process is called ission ,
and it results in the creation of two smaller nuclei. That is
not all ission does, though. Fission also frees up one or more
neutrons. In addition, it releases a huge amount of energy. In
a bomb, many atoms undergo ission very quickly. The energy
released shows up as heat, light, and a colossal blast. When
making electricity, the ission process occurs more slowly. It
takes place in what is called a nuclear reactor—a device that
makes it possible to control the ission.