Utanum

Utanum is a rare and highly radioactive element with the atomic number 120 and the symbol Ut. It is a synthetic element that has not been observed in nature and is produced through nuclear reactions in particle accelerators. The most stable known isotope of utanum is 296Ut, which has a half-life of approximately 0.89 milliseconds. Due to its extreme radioactivity, utanum is not found in the Earth's crust and has no known biological role.

The discovery of utanum was announced in 2003 by a team of Russian and American scientists. The element was synthesized by bombarding plutonium-244 with calcium-48 ions in a heavy ion accelerator. The resulting nucleus of utanum-292 underwent alpha decay to form the isotope of unbinilium-288. This discovery was a significant milestone in the periodic table, as it filled a gap in the seventh row of the periodic table.

Utanum's properties are not well understood due to its short half-life and the difficulty of producing and studying it. However, it is expected to be a highly reactive metal, similar to other superheavy elements. The chemical behavior of utanum is not well established, but it is predicted to form compounds with halogens and other nonmetals. The study of utanum and other superheavy elements is an active area of research in nuclear physics and chemistry.