Rhodium (Rh) – element 45
Rhodium is a chemical element with the symbol Rh and atomic number 45. It is a transition metal in group 9, period 5 of the periodic table (d-block), and is a solid at room temperature.
Rhodium (Rh) has atomic number 45, atomic mass 102.91 u and electron configuration [Kr] 4d8 5s1.
Rhodium facts
| Symbol | Rh |
|---|---|
| Atomic number | 45 |
| Atomic mass | 102.91 u (g/mol) |
| Category | transition metal |
| Group | group 9 |
| Period | 5 |
| Block | d-block |
| Phase at 20 °C | Solid |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d8 |
| Noble-gas notation | [Kr] 4d8 5s1 |
| Electrons per shell | 2, 8, 18, 16, 1 |
Bohr model and shells
Rhodium has 45 electrons in 5 shells: 2, 8, 18, 16, 1. Full configuration and noble-gas notation are in the table; work out any element or ion with the electron configuration calculator.
Physical and atomic properties
| Melting point | 2237 K (1963.8 °C) |
|---|---|
| Boiling point | 3968 K (3694.8 °C) |
| Density | 12.41 g/cm³ |
| Electronegativity (Pauling) | 2.28 |
| Electron affinity | 110.27 kJ/mol |
| Ionization energies | 719.7, 1740, 2997 kJ/mol (1st, 2nd, 3rd) |
| Molar heat capacity | 24.98 J/(mol·K) |
| Discovered by | William Hyde Wollaston |
Use the atomic mass in the molar mass calculator for any formula containing Rh.
Position in the periodic table
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Frequently asked questions
What is the atomic mass of rhodium?
The atomic mass of rhodium is 102.91 u, so one mole of rhodium atoms weighs 102.91 g.
What is the electron configuration of rhodium?
Rhodium has 45 electrons: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s¹ 4d⁸, or [Kr] 4d⁸ 5s¹ in noble-gas notation. Electrons per shell: 2, 8, 18, 16, 1.
Is rhodium a metal?
Yes. Rhodium is a transition metal.
Where is rhodium on the periodic table?
Rhodium is in group 9, period 5, in the d-block.
Data: Periodic-Table-JSON (CC BY-SA 3.0); standard atomic weights from IUPAC (abridged). Values in brackets are the mass number of the longest-lived isotope.