Because uranium atoms are so large, the atomic force that binds it together is relatively weak, making uranium good for fission. In nuclear power plants, neutrons collide with uranium atoms, splitting them. This split releases neutrons from the uranium that in turn collide with other atoms, causing a chain reaction.This chain reaction is controlled with control rods that absorb neutrons.n the core of nuclear reactors, the fission of uranium atoms releases energy that heats water to about 520 degrees Farenheit. This hot water is then used to spin turbines that are connected to generators, producing electricity.