Meitnerium

Atomic symbol: Mt
Atomic number: 109
Atomic mass: 278

Appearance: Solid at 25°C

Group: 9
Period: 7
Series: Transition metals
Block: d
Electron configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p⁶ 5f¹⁴ 6d⁷ 7s²

A superheavy, transactinide, radioactive and synthetic metal.

Fun Fact! Meitnerium-278, the most stable meitnerium isotope, has an incredibly short half-life of only 4.5 seconds!

Meitnerium is one of few elements to be named after a female scientist, Lise Meitner, who discovered nuclear fission.

https://en.wikipedia.org/wiki/Meitnerium https://www.chemicool.com/elements/meitnerium.html