Manganese (symbol Mn, atomic number 25) is an essential steel-making additive and a component of dry-cell batteries. It is classified as a transition metal and sits in group 7, period 4 of the periodic table.
Overview
Manganese is the chemical element with atomic number 25 and the symbol Mn. With a standard atomic weight of 54.938, it is a transition metal. In the periodic table it occupies group 7 and period 4, and under standard conditions it is normally a solid. Manganese is an essential steel-making additive and a component of dry-cell batteries.
Atomic structure
An atom of Manganese has 25 protons in its nucleus and, when neutral, 25 electrons arranged in the configuration [Ar] 3d5 4s2. Its standard atomic weight of 54.938 reflects the natural mix of its stable isotopes.
Discovery and place in the table
Manganese was discovered in 1774 by Johan Gottlieb Gahn. It follows Chromium (Cr) and precedes Iron (Fe) in order of atomic number.
| Atomic number | 25 |
|---|---|
| Symbol | Mn |
| Atomic mass | 54.938 |
| Category | Transition metal |
| Group | 7 |
| Period | 4 |
| Electron configuration | [Ar] 3d5 4s2 |
| Phase at STP | Solid |
| Discovered | 1774 (Johan Gottlieb Gahn) |