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Rh

Rhodium

Atomic number: 45Mass: 102.906 uCategory: Transition Metal

About Rhodium

Rhodium is a hard, silvery, durable metal that has a high reflectance. It is in the platinum group and is one of the rarest and most valuable precious metals on Earth.

Properties

Period
5
Group
9
Block
D
Category
Transition Metal
Electronegativity
2.28 (Pauling)
Ionization Energy
719.7 kJ/mol
Melting Point
2237 K (1964°C)
Boiling Point
3968 K (3695°C)
Density
12.41 g/cm³
Oxidation States
+3

Electron Configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d⁸ 5s¹
[Kr] 4d⁸ 5s¹
Shell 1:2e⁻
Shell 2:8e⁻
Shell 3:18e⁻
Shell 4:16e⁻
Shell 5:1e⁻

Real-World Uses

Catalytic converters
Jewellery plating
Reflective mirrors
Thermocouples
Electrical contacts

Fun Fact

Rhodium is the most expensive metal in the world — far more costly than gold or platinum — and your car's catalytic converter uses it!