Mt
Meitnerium
Element 109 · Transition metal
Meitnerium (Mt)
Meitnerium is a synthetic, highly radioactive element. Its first detection rested on a single atom.
- Transition metal
- Period 7
- Group 9
- d-block
- solid at room temperature
- ☢ Radioactive
Key properties
- Atomic mass
- [277]
- u
- Electron configuration
- [Rn] 5f14 6d7 7s2
- Melting point
- —
- Boiling point
- —
- Density
- 37.4 g/cm³
- Electronegativity
- —
- Atomic radius
- —
- 1st ionisation energy
- —
Superheavy elements have only been made a few atoms at a time. Most properties shown are theoretical predictions.
Compare with every element:Electronegativity chartAtomic radius chartIonisation energy chartDensity chart of the elementsMelting point chartElectron configuration chart
Did you know?
Notable facts about meitnerium
- 01
It was first identified from just one atom.
- 02
Meitner was overlooked for the Nobel Prize given for fission; the element honours her work.
- 03
Its chemistry has never been studied experimentally.
Applications
What is meitnerium used for?
- Research
History
Discovery & name origin
Discovered by
Year
Where
Germany
Name origin
From Lise Meitner, co-discoverer of nuclear fission.
Atomic structure
Atomic properties
Atomic structure
Atomic properties
- Atomic number
- 109
- Atomic mass
- [277] u
- Group
- 9
- Period
- 7
- Block
- d-block
- Electron configuration
- [Rn] 5f14 6d7 7s2
- Full configuration
- 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d7
- Electrons per shell
- 2, 8, 18, 32, 32, 15, 2
- Electronegativity (Pauling)
- —
- Electron affinity
- —
- Atomic radius (van der Waals)
- —
- Stable isotopes
- None — all isotopes are radioactive
Oxidation states
Highlighted: common oxidation states (+9, +8, +6, +4, +3, +1).
Physical
Physical properties & colour
Physical
Physical properties & colour
- State at 20 °C
- Solid (predicted)
- Melting point
- —
- Boiling point
- —
- Density
- 37.4 g/cm³
- Molar heat capacity
- —
- Appearance
- —
- CPK model colour
- Copied
The CPK colour is the convention used for this element’s atoms in molecular models.
FAQ
Meitnerium questions
What is Mt on the periodic table?
Mt is the symbol for meitnerium, element 109 on the periodic table. It sits in group 9, period 7, in the transition metal category, and has an atomic mass of [277].
What is the atomic number of meitnerium?
Meitnerium has atomic number 109, so every meitnerium atom has 109 protons in its nucleus. Its symbol is Mt and its atomic mass is [277].
Who discovered meitnerium?
Meitnerium was discovered by Peter Armbruster and Gottfried Münzenberg in 1982 (Germany). The name comes from from Lise Meitner, co-discoverer of nuclear fission.
What is meitnerium used for?
Meitnerium is used for: research.
Is meitnerium a metal?
Yes. Meitnerium is a transition metal, one of the metallic elements.
What is the electron configuration of meitnerium?
The electron configuration of meitnerium is [Rn] 5f14 6d7 7s2 (predicted). Its 109 electrons are arranged in shells as 2, 8, 18, 32, 32, 15, 2.