Meitnerium (Mt)
Meitnerium is element 109, a transition metal in period 7, group 9 of the periodic table. At room temperature it is of unknown state (too few atoms have ever been made).
Electron configuration [Rn] 5f14 6d7 7s2
Electrons per shell 2, 8, 18, 32, 32, 15, 2
Meitnerium data
| Atomic number | 109 |
|---|---|
| Symbol | Mt |
| Atomic mass | [276] (mass number of the longest-lived isotope) |
| Category | Transition metal |
| Group | 9 |
| Period | 7 |
| Block | d |
| State at 25 °C | unknown |
| Melting point | — |
| Boiling point | — |
| Density | — |
| Electronegativity (Pauling) | — |
| Atomic radius | — |
| 1st ionization energy | — |
| Electron affinity | — |
| Oxidation states | 0 |
| Common ion charge | — |
| Discovered | 1982 |
Orbital diagram
Each box is one orbital holding up to two electrons of opposite spin. Following Hund’s rule, electrons spread out singly across a subshell before pairing.
Work through meitnerium’s configuration and its ions →
Where meitnerium sits
Meitnerium belongs to the transition metals. To use its mass in a calculation, try the molar mass calculator.
Meitnerium FAQ
What is the electron configuration of meitnerium?
Meitnerium (Z = 109) has the configuration 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d7 7s2. In noble-gas shorthand that is [Rn] 5f14 6d7 7s2.
How many valence electrons does meitnerium have?
9 (2 outer s + 7 d electrons; 2 in the outermost shell).
What is the atomic mass of meitnerium?
Meitnerium has no stable isotopes. Its most stable known isotope has mass number 276, so tables list [276].
Is meitnerium a metal?
Yes. Meitnerium is a transition metal.