The element known for its significant role in nuclear reactions is uranium. Uranium, specifically the isotope uranium-235, is a key fuel used in nuclear reactors and is also employed in the production of nuclear weapons. In nuclear fission, the nucleus of a uranium atom is split into smaller parts, releasing a tremendous amount of energy, which can be harnessed for electricity generation or weaponry. Due to its radioactive properties, uranium must be handled with caution, and its mining and use raise important safety and environmental concerns.