Periodic Table · element

Meitnerium

Mt · Z 109

atomic number

109

atomic mass

278

notation

Mt

group

9: Cobalt

period

7

state0c

Solid

state20c

Unknown

occurrence

Synthetic

discovered

1982

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From the All Periodical Elements database in Notion, last edited 2026-08-13. This page is the row, rendered by the build; nothing on it is written by hand.