45
Rh
Rhodium
102.9055
Rhodium (Rh)
Transition MetalGroup 9Period 5d-block-block
Rhodium is a chemical element with symbol Rh and atomic number 45. It is a rare, silvery-white, hard, and chemically inert transition metal. It is a member of the platinum group.
Latin name: Rhodium
Atomic Number
45
Atomic Mass
102.9055 g/mol
Phase (STP)
Solid
Electron Config.
[Kr] 4d⁸ 5s¹
General
SymbolRh
Atomic Number45
Atomic Mass102.9055 g/mol
CategoryTransition Metal
Group9
Period5
Blockd-block
Electron Configuration[Kr] 4d⁸ 5s¹
Valence Electrons9
Coloursilvery-white metallic
Appearancesilvery white metallic
CAS NumberCAS7440-16-6
Physical Properties
Phase (STP)Solid
Density12.41 g/cm³
Melting Point1963.85°C · 3566.93°F · 2237.00 K
Boiling Point3694.85°C · 6682.73°F · 3968.00 K
Atomic Properties
Atomic Radius173 pm
Electronegativity2.28 Pauling
Ionization Energy720 kJ/mol
Oxidation States+3, +4, +1
Ion ChargeRh3+/Rh4+
Thermodynamic
Molar Heat24.98 J/(mol·K)
Crystal Structure
Crystal Structureface-centered cubic
Mechanical Properties
Mohs Hardness6
Abundance
In Universe0.000007%
In Sun0.000005%
In Earth's Crust0.0000001%
Discovery & History
Discovery Year1803
Discovered ByWilliam Hyde Wollaston
Country of DiscoveryEngland
Isotopes of Rhodium
| Isotope | Abundance | Half-life | Decay |
|---|---|---|---|
| Rh-103 | 100% | Stable | — |