109Mt
Meitnerium
Meitnerium (Mt) is element 109, a synthetic superheavy element whose chemical properties are still unconfirmed, in period 7 and group 9 of the periodic table. Its atomic mass is usually given as 278. Discovered by GSI, 1982.
Atomic Number109
SymbolMt
NameMeitnerium
Atomic Weight278 u
Period7
Group9
Electron Config[Rn] 5f14 6d7 7s2
Discovered ByGSI, 1982