Rhodium (Rh)

Rhodium is a chemical element of the periodic table with chemical symbol Rh and atomic number 45 with an atomic weight of 102.906 u and is classed as transition metal and is part of group 9 (cobalt group). Rhodium is solid at room temperature.

Ruthenium Periodic table Palladium

Rhodium in the periodic table

Symbol	Rh
Atomic number	45
Group	9 (Cobalt group)
Period	5
Block	d
Classification	Transition Metal

Appearance	Silvery white metallic
Color	Silver

Number of protons	45 p⁺
Number of neutrons	58 n⁰
Number of electrons	45 e^-

From Wikipedia, the free encyclopediaRhodium 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.

Physical properties

Phase at STP	Solid
Density	12.41 g/cm³
Atomic weight	102.906 u

Thermal properties

Melting point	2237 K 1963.85 °C 3566.93 °F
Boiling point	3968 K 3694.85 °C 6682.73 °F
Heat of vaporization	495.39 kJ/mol

Atomic properties

Electronegativity (Pauling Scale)	2.28
Electron affinity	110.27 kJ/mol
Oxidation states	−3, −1, 0, +1, +2, +3, +4, +5, +6 (an amphoteric oxide)
Ionization energies	719.7 kJ/mol 1740 kJ/mol 2997 kJ/mol

Electron configuration for rhodium

Electron configuration

Shorthand configuration

[Kr] 4d⁸ 5s¹

Electron configuration

Full configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d⁸ 5s¹

Electron configuration chart

1s²
2s²	2p⁶
3s²	3p⁶	3d¹⁰
4s²	4p⁶	4d⁸
5s¹

Electrons per shell

2, 8, 18, 16, 1

Valence electrons

9

Valency electrons

3

Bohr model

Figure: Shell diagram of Rhodium (Rh) atom.

Orbital Diagram

1s
2s	2p
3s	3p	3d
4s	4p	4d
5s

The history of Rhodium

Discovery and first isolation	William Hyde Wollaston (1804)
Discovery of rhodium Rhodium is found in platinum or nickel ores with the other members of the platinum group metals. Rhodium (Greek rhodon (ῥόδον) meaning "rose") was discovered in 1803 by William Hyde Wollaston, soon after he discovered palladium. Rodium is named for the rose color of one of its chlorine compounds.

Periodic table history

Identifiers

List of unique identifiers for Rhodium in various chemical registry databases

CAS Number	7440-16-6
ChemSpider ID	22389
EC number	231-125-0
PubChem CID Number	23948