Comparison of Ruthenium and Iridium

Attribute	Iridium ×	Ruthenium ×
Atomic mass (u)	192.22	101.1
Standard state	Solid	Solid
Oxidation states	+3 +4	+3
Electron configuration	[Xe]6s²4f¹⁴5d⁷	[Kr]5s¹4d⁷
Atomic radius (van der waals) (pm)	202	207
Electronegativity (pauling scale)	2.2	2.2
Electron affinity (eV)	1.565	1.05
Ionization energy (eV)	9.1	7.361
Boiling point (K)	4701	4423
Melting point (K)	2719	2607
Density (g/cm³)	22.42	12.1
Atomic number	77	44
Group name	Transition metal	Transition metal
Discovered (year)	1803	1827
Symbol	Ir	Ru