Bohrium (Bh)
Transition metal · Radioactive · Synthetic
Bohrium honours Niels Bohr, whose atomic model underpins the whole periodic table. Made atom by atom by fusing chromium into bismuth, it behaves chemically like a heavy rhenium.
Position on the periodic table
Atomic properties
| Atomic number | 107 |
|---|---|
| Atomic mass | 270 amu |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d5 |
| Noble gas shorthand | *[Rn] 5f14 6d5 7s2 |
| Electrons per shell | 2, 8, 18, 32, 32, 13, 2 |
| Valence electrons (outer shell) | 2 |
| Common oxidation states | +7 |
| Electronegativity (Pauling) | Not available |
| Covalent radius (approx.) | Not available |
| First ionization energy | Not available |
| Electron affinity | Not available |
Physical properties
| State at 25 °C | Solid |
|---|---|
| Density | 37.1 g/cm³ |
| Melting point | Not available |
| Boiling point | Not available |
| Appearance | Not available |
| Radioactive | Yes |
| Origin | Synthetic (lab-made) |
Electron configuration of bohrium
Bohrium's ground-state electron configuration is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d5, usually shortened to *[Rn] 5f14 6d5 7s2. Its electrons occupy 7 shells (2, 8, 18, 32, 32, 13, 2), placing it in period 7 of the d-block. Explore it interactively in the electron configuration calculator.
Uses of bohrium
- Fundamental research only
Biological role: None.
Occurrence: Entirely synthetic.
History and discovery
Discovered: 1981 — Gesellschaft für Schwerionenforschung. Name origin: Named after Niels Bohr.
First convincingly made at GSI Darmstadt, Germany, in 1981 using the “cold fusion” technique.
Safety notes
Radioactive; exists for seconds.
Educational context only — always follow your school's laboratory rules and never handle chemicals without proper supervision. See our disclaimer.
Practice questions
Quick practice: Bohrium
1. What is the chemical symbol of Bohrium?
2. What is the atomic number of Bohrium?
3. Which category does Bohrium belong to?
4. What is the state of Bohrium at room temperature?
5. Which period of the periodic table is Bohrium in?
Bohrium FAQs
What is the atomic number of bohrium?
Bohrium's atomic number is 107 — every bohrium atom has 107 protons in its nucleus.
What is the symbol for bohrium?
Bh. Named after Niels Bohr.
Is bohrium a metal, nonmetal, or metalloid?
Bohrium is classified as a transition metal.
What state is bohrium at room temperature?
At about 25 °C, bohrium is a solid.
What is bohrium used for?
Key uses include: fundamental research only.
Related elements
Keep working with this element
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