Element 109
Meitnerium
Transition metals
Meitnerium (Mt) is in the d-block of the periodic table — group 9, period 7.
Meitnerium is a chemical element with symbol Mt and atomic number 109.
Key data
- Atomic number
- 109
- Atomic mass
- 278.000 u
- Group / Period
- 9 / 7
- Block
- d-block
- Phase at STP
- Solid
- Density
- 37.4 g/cm³
- Melting point
- —
- Boiling point
- —
- Electron configuration
- *[Rn] 5f14 6d7 7s2
Periodic table block
Meitnerium is in the d-block (group 9, period 7). Elements land in the d-block when their highest-energy electrons fill a d subshell — these are the transition metals in the middle of the table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •Research only
- •Named after Lise Meitner
- •Synthesized 1982
Discovery
Year: 1982
Discovered by: Gesellschaft für Schwerionenforschung
Frequently asked questions
What is the atomic number of Meitnerium?
Meitnerium has atomic number 109. Its symbol is Mt and its atomic mass is 278 u.
What category of element is Meitnerium?
Meitnerium is classified as transition metals. It sits in group 9, period 7 of the periodic table.
What block of the periodic table is Meitnerium in?
Meitnerium is in the d-block (group 9, period 7). Its highest-energy electrons occupy the d subshell — you can see this in its electron configuration, *[Rn] 5f14 6d7 7s2.
What is Meitnerium used for?
Common uses of Meitnerium include: Research only, Named after Lise Meitner, Synthesized 1982.
When was Meitnerium discovered?
Meitnerium was discovered in 1982 by Gesellschaft für Schwerionenforschung.
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