Prometthium: The Periodic Table
Promethium, Pm, is the 61st element on the Periodic Table. It was discovered in 1945 by Jacob A. Marinsky. It’s a metal, and named after the Greek God Prometheus. It is not naturally occurring, but can survive outside of a lab.
Promethium has an atomic number of 61, which is the number of protons. Its atomic mass, protons+neutrons, is 145u. It is an isotope. This means that it has a different number of neutrons (84) than the number of electrons and protons (61). Every element changes states of matter at different temperatures. Promethium melts at 1042.0°C (1315 Kelvin), boils at 3000.0°C (3273 Kelvin), and freezes at 931.0°C. Its normal phase is synthetic, but is used as a solid or liquid. Promethium costs $0.50 per Curie. A Curie (Ci)
Promethium has an atomic number of 61, which is the number of protons. Its atomic mass, protons+neutrons, is 145u. It is an isotope. This means that it has a different number of neutrons (84) than the number of electrons and protons (61). Every element changes states of matter at different temperatures. Promethium melts at 1042.0°C (1315 Kelvin), boils at 3000.0°C (3273 Kelvin), and freezes at 931.0°C. Its normal phase is synthetic, but is used as a solid or liquid. Promethium costs $0.50 per Curie. A Curie (Ci)