Uranium is the last and heaviest of the natural elements.
Most people associate it with nuclear reactors and atomic bomb as a source of enormous energy.
Uranium is a dense, soft, silver-white radioactive metal that quickly acquires a dark oxide coating when exposed to air. It is reactive and electropositive, reacting with hot water and dissolving in acids. Neutron capture by U 235 leads to nuclear fission, and a chain reaction can occur which is the basis of nuclear reactors and atomic bomb.