renium

Reinum is a chemical element with the atomic number 75 and the symbol Rf. It is a synthetic, radioactive, and highly unstable element that belongs to the group 7 of the periodic table.

Reinum was first synthesized in 1969 by Soviet physicists at the Joint Institute for Nuclear Research in Dubna, Russia. The team, led by scientist Georgy Flerov, used the collision of calcium-48 and nickel-59 nuclei to create a few atoms of the element. Since then, scientists have successfully created several other isotopes of reinum through various methods of nuclear fusion and fission.

Reinum has an atomic mass ranging from 260 to 294, depending on the specific isotope. Due to its highly unstable nature, reinum decays rapidly into lighter elements, with decay half-life ranging from a few milliseconds to a few hours. Its isotopes primarily decompose to niobium, palladium, and krypton, shedding alpha particles in the process.

In terms of physical properties, reinum exists as a post-transition metal and has not been isolated in large quantities due to its extreme radioactivity. As such, its chemical behavior and physical characteristics have not been extensively studied. The most stable known isotope, rutherfordium-267, is produced in amounts of about 10 milligrams per experiment.

Reinum was officially recognized as an element by the IUPAC (International Union of Pure and Applied Chemistry) in 1992, following several positional disputes and reports of conflicting synthesis claims. Today, its study and production continue in nuclear chemistry and particle physics laboratories.