Bohrium
Bohrium (Bh, atomic number 107) is a Period 7 transition metal (d-block, 270 u). Named after Niels Bohr, pioneer of quantum atomic structure. Single-atom thermochromatography demonstrated that BhO₃Cl behaves as a Group 7 homolog of Rhenium.
Bohrium is a chemical element on the periodic table with the atomic symbol Bh, atomic number 107, and standard atomic weight 270 u. Classified as a Transition Metal within Group 7 and Period 7 (d-block), bohrium possesses a ground-state electron configuration of [Rn] 5f14 6d5 7s2 distributed across 7 concentric Bohr electron shells (2 · 8 · 18 · 32 · 32 · 13 · 2) with 2 outer-shell electrons. Named after Niels Bohr, pioneer of quantum atomic structure. Single-atom thermochromatography demonstrated that BhO₃Cl behaves as a Group 7 homolog of Rhenium.
⚛️ Interactive Periodic Table Lab: Explore Bohrium (Bh, Z = 107) in the CRV Science Dynamic Periodic Table & Bohr Orbital Lab to visualize its animated 2 · 8 · 18 · 32 · 32 · 13 · 2 electron shells, simulate live phase transitions from 0 K to 6,000 K, and compare periodic heatmaps across all 118 IUPAC elements.
Atomic Structure and Periodic Trends: How Do Quantum Orbitals Define Bohrium?
Electron Shell Architecture and Ground-State Configuration
A neutral atom of bohrium contains 107 protons in its atomic nucleus balanced by 107 electrons occupying quantized atomic orbitals. In the Bohr-Sommerfeld and quantum-mechanical orbital models, these electrons populate 7 principal energy shells (K (n=1): 2e−, L (n=2): 8e−, M (n=3): 18e−, N (n=4): 32e−, O (n=5): 32e−, P (n=6): 13e−, Q (n=7): 2e−), terminating in the four-lobed d-orbital manifold (azimuthal quantum number l = 2) with ground-state configuration [Rn] 5f14 6d5 7s2. Removing the most loosely bound valence electron from an isolated gaseous bohrium atom requires a first ionization energy of 740 kJ/mol, while its tendency to attract shared bonding electrons is quantified by a Pauling electronegativity of N/A (closed-shell or superheavy regime).
Periodic Table Position and Neighboring Elements
Within the periodic table, Bohrium occupies Period 7, Group 7 of the d-block (Transition Metals). Along Period 7, it is flanked by Seaborgium (Sg, Z = 106) and Hassium (Hs, Z = 108). Vertically within its periodic family, Bohrium shares valence orbital symmetry and homologous chemical trends with Manganese (Mn), Technetium (Tc), Rhenium (Re). Learners can interactively compare Bohrium's orbital radii, ionization energy, and Pauling electronegativity against all neighboring elements in the Dynamic Periodic Table Lab.
Physical and Thermodynamic Properties: How Does Bohrium Behave Across Temperature Regimes?
Standard Phase, Melting Point, and Boiling Point Dynamics
At standard ambient temperature and pressure (298.15 K / 25 °C, 1 atm), elemental bohrium exists as a short-lived synthetic phase. As thermal energy increases, its crystal or molecular lattice undergoes solid-to-liquid fusion at a melting point of Unknown (predicted synthetic regime) and transitions to the vapor phase at a normal boiling point of Unknown (predicted synthetic regime), spanning a liquid thermodynamic range of N/A (sublimes or synthetic regime). In the CRV Science Dynamic Periodic Table, dragging the live temperature slider between absolute zero (0 K) and solar-photosphere temperatures (6,000 K) dynamically tracks Bohrium's state transitions in real time alongside enthalpy and entropy phase equilibria.
Quantitative Atomic and Thermodynamic Parameter Matrix
| Parameter | Quantitative Value / Formula | Physical / Quantum Basis | Comparative Context in Group 7 / Period 7 |
|---|---|---|---|
| Atomic Number & Symbol | Z = 107 (Bh) | 107 nuclear protons; nuclear charge +107e | Located in Period 7, Group 7 (d-block) |
| Standard Atomic Weight | 270 u (g/mol) | Abundance-weighted isotopic nucleon mass | ~163 neutrons in dominant/reference mass number |
| Electron Configuration | [Rn] 5f14 6d5 7s2 | Shells: 2 · 8 · 18 · 32 · 32 · 13 · 2 (2 outer-shell e−) | Transition Metals valence orbital architecture |
| Electronegativity & Ionization | χ = N/A; IE1 = 740 kJ/mol | Pauling bond polarity scale & first valence ionization enthalpy | Governs covalent vs. ionic bond character |
| Melting & Boiling Points | MP: Unknown; BP: Unknown | Cohesive lattice energy and intermolecular forces | STP (298 K) phase: UNKNOWN (Liquid range: N/A (sublimes or synthetic regime)) |
| Principal Oxidation States | +7 | Valence electron donation, sharing, or acceptance | Discovered / First Isolated: 1981 |
Chemical Reactivity, Bonding, and Oxidation States: How Does Bohrium Form Compounds?
Characteristic Oxidation States and Coordination Chemistry
As a d-block transition metal, partially filled (n−1)d orbitals lie close in energy to the outermost ns subshell, enabling variable oxidation states, d–d electronic transitions, coordination complex formation, and heterogeneous or metalloenzymatic redox catalysis. In chemical compounds, bohrium exhibits characteristic oxidation states of +7. Depending on the electronegativity difference (Δχ) of its bonding partners—such as Oxygen (χ = 3.44), Fluorine (χ = 3.98), Chlorine (χ = 3.16), Nitrogen (χ = 3.04), Carbon (χ = 2.55), or Hydrogen (χ = 2.20)—bohrium forms redox-specific oxides, halides, hydrides, or coordination complexes governed by Gibbs free energy (ΔG = ΔH − TΔS).
Nucleosynthesis, Discovery History, and Elemental Origins
First identified or isolated in 1981, Bohrium carries a distinct cosmological and geochemical signature. As a synthetic transuranic element (Z = 107), bohrium does not persist in primordial terrestrial minerals and is produced atom-by-atom in nuclear reactors or heavy-ion particle accelerators.
Biological Role and Scientific Applications: Why Is Bohrium Important in Nature and Technology?
Biochemical Classification: Abiotic / Technological / Synthetic
In comparative biochemistry and systems physiology, Bohrium is classified as Abiotic / Technological / Synthetic. No known essential biological role; important in planetary geochemistry, astrophysics, materials science, or nuclear physics. Across terrestrial and marine ecosystems, its chemical speciation interacts with thermodynamics, enthalpy, entropy, chemistry.
Key Mechanistic Functions and Technological Uses
Named after Niels Bohr, pioneer of quantum atomic structure. Single-atom thermochromatography demonstrated that BhO₃Cl behaves as a Group 7 homolog of Rhenium. Researchers and students can further investigate Bohrium's functional role alongside all 118 elements by launching the Interactive Periodic Table & Element Detective Lab on CRV Science Learn.
Frequently Asked Scientific Questions
What is the electron configuration and valence shell structure of Bohrium (Bh)?
Bohrium (atomic number Z = 107) has the ground-state electron configuration [Rn] 5f14 6d5 7s2, distributing its 107 electrons across 7 shells as 2 · 8 · 18 · 32 · 32 · 13 · 2. Its outermost shell contains 2 electrons, placing Bohrium in Group 7, Period 7 (d-block) as a member of the Transition Metals. You can watch these 107 electrons orbit the nucleus in real time in the Dynamic Periodic Table Bohr Lab.
What phase of matter is Bohrium at room temperature, and when does it melt or boil?
At standard room temperature (298 K / 25 °C) and 1 atm pressure, Bohrium is a short-lived synthetic phase. It melts at Unknown (predicted synthetic regime) and boils at Unknown (predicted synthetic regime). Using the 0–6,000 K temperature slider in the Interactive Periodic Table, you can observe Bohrium's exact solid, liquid, and gas transitions relative to all other elements.
How does Bohrium function in biochemistry, materials science, and technology?
Named after Niels Bohr, pioneer of quantum atomic structure. Single-atom thermochromatography demonstrated that BhO₃Cl behaves as a Group 7 homolog of Rhenium. In biological systems, it is categorized under Abiotic / Technological / Synthetic, with principal oxidation states of +7 and a first ionization energy of 740 kJ/mol.