Uranium-235
Discovery and Isolation
Uranium-235 was first discovered in the early 1930s, when Fermi and his team of scientists were conducting experiments on various elements. The discovery of Uranium-235 was a significant milestone in the field of nuclear physics, as it was the first isotope found to be capable of sustaining a nuclear chain reaction.
Physical Properties
Uranium-235 is a heavy, radioactive isotope of uranium. It has 92 protons and 143 neutrons in its nucleus, giving it an atomic mass of approximately 235.04 atomic mass units. It is a silver-grey metal in its solid state and has a melting point of 1132.2 degrees Celsius.
Chemical Properties
Uranium-235, like all isotopes of uranium, is a highly reactive metal. It reacts readily with oxygen, forming uranium dioxide (UO2) or uranium trioxide (UO3). It also reacts with acids but not with alkalis.
Radioactive Decay
Uranium-235 undergoes radioactive decay and is known for its ability to sustain a nuclear chain reaction. It decays through alpha decay into Thorium-231. The half-life of Uranium-235 is approximately 703.8 million years, which is shorter than that of Uranium-238, making it more radioactive.
Uses
Uranium-235 is primarily used as a fuel in nuclear reactors due to its ability to sustain a nuclear chain reaction. It is also used in the production of nuclear weapons.
Health Effects
Exposure to Uranium-235 can have serious health effects. It can cause kidney damage if ingested or inhaled, and its radioactivity poses risks of cancer and genetic damage.