Manganese Element Properties
Complete reference for Manganese (Mn, element 25): atomic data, electron configuration, oxidation states, physical constants, and chemical behavior.
Manganese
Transition Metal — Period 4, Group 7
Atomic Identity
Electron Configuration
Manganese has a half-filled 3d subshell with one electron in each 3d orbital (Hund's rule maximum), plus a full 4s² pair. This gives five unpaired electrons and the highest spin multiplicity of the first-row transition metals up to Mn.
5 unpaired electrons — strongly paramagnetic
Physical Properties
Chemical Properties
Oxidation States in Detail
| State | Key Compounds | Color | Notes |
|---|---|---|---|
| +7 | KMnO₄ (permanganate), Mn₂O₇ | Intense violet/purple | Strongest oxidizer; acidic permanganate is a powerful analytical reagent |
| +6 | K₂MnO₄ (manganate) | Green | Stable only in strongly alkaline solution; disproportionates at neutral pH |
| +4 | MnO₂ (pyrolusite), MnF₄ | Black/brown | Most stable binary oxide; used in dry-cell batteries and as oxidant |
| +3 | Mn₂O₃, MnF₃, Mn(acac)₃ | Black / dark red | Oxidizing; important in biological manganese enzymes (superoxide dismutase) |
| +2 | MnO, MnCl₂, MnSO₄, Mn²⁺(aq) | Pale pink | Most stable aqueous state; very common in salts and coordination chemistry |
| 0 | Mn₂(CO)₁₀ (dimanganese decacarbonyl) | Yellow | Organometallic; used in research and as a fuel additive (MMT) |
Key Facts About Manganese
Essential Steelmaking Metal
Manganese is a critical additive in steelmaking. It deoxidizes the melt, removes sulfur (forming MnS instead of brittle FeS), and boosts strength, hardness, and wear resistance. Nearly 90% of all manganese mined is used in steel.
Permanganate Oxidizer
Potassium permanganate (KMnO₄) is one of the most versatile oxidants in organic chemistry and water treatment. The intensely violet MnO₄⁻ ion is reduced to Mn²⁺ (acid) or MnO₂ (neutral/basic), releasing 5 or 3 electrons per ion.
Photosynthesis Role
The oxygen-evolving complex (OEC) in photosystem II contains a Mn₄CaO₅ cluster. This cubane-like structure cycles through five oxidation states (S0–S4) to split two water molecules, releasing O₂ — the source of almost all atmospheric oxygen.
Dry-Cell Batteries
MnO₂ is the cathode material in standard alkaline (Zn/MnO₂) batteries and the original carbon-zinc (Leclanché) cell. It accepts electrons during discharge, being reduced from Mn(IV) to Mn(III). Global battery demand drives significant MnO₂ production.
Widest Oxidation Range
Manganese displays oxidation states from -3 to +7 — the broadest range of any 3d transition metal. This versatility arises from the near-degenerate 3d and 4s orbitals and the stability of the half-filled 3d⁵ configuration at the midpoint.
Discovered 1774
Swedish chemist Johan Gottlieb Gahn first isolated manganese metal in 1774 by reducing pyrolusite (MnO₂) with carbon. The name derives from the Greek "Magnesia," the region where manganese ores were found in antiquity.
Summary
Complete reference for Manganese (Mn, element 25): atomic data, electron configuration, oxidation states, physical constants, and chemical behavior.
How it works
- Browse the atomic identity section for symbol, atomic number, and standard atomic weight.
- Check the electron configuration panel for the [Ar] 3d⁵ 4s² notation.
- Review the physical properties panel for density, melting point, boiling point, and crystal structure.
- Consult the chemical properties section for electronegativity, ionization energies, and oxidation states.
- Explore the oxidation states panel to understand the full +7 to -3 range of manganese chemistry.
- Click any value to copy it to the clipboard for use in reports or calculations.
Use cases
- Look up manganese constants for chemistry homework or exams.
- Verify atomic data when writing lab reports on transition metals.
- Reference electron configuration for d-block chemistry studies.
- Check physical properties for materials science and metallurgy applications.
- Understand manganese oxidation states for inorganic or analytical chemistry.
- Confirm electronegativity and ionization energy for bond analysis.
- Reference manganese data for environmental chemistry and biochemistry studies.
- Teach or learn about permanganate oxidations and MnO₂ redox chemistry.