Iridium

Iridium, ₇₇Ir

Iridium
Pípè	/ɪˈrɪdiəm/ ​(i-RID-ee-əm)
Ìhànsójú	silvery white
Ìwúwo átọ̀mù Ar, std(Ir)	192.217(2)
Iridium ní orí tábìlì àyè
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson Rh ↑ Ir ↓ Mt osmium ← iridium → platinum
Nọ́mbà átọ̀mù (Z)	77
Ẹgbẹ́	group 9
Àyè	àyè 6
Àdìpọ̀	Àdìpọ̀-d
Ẹ̀ka ẹ́límẹ́ntì	Transition metal
Ìtò ẹ̀lẹ́ktrọ́nù	[Xe] 4f14 5d7 6s2
Iye ẹ̀lẹ́ktrọ́nù lórí ìpele kọ̀ọ̀kan	2, 8, 18, 32, 15, 2
Àwọn ohun ìní ara
Ìfarahàn at STP	solid
Ìgbà ìyọ́	2739 K ​(2466 °C, ​4471 °F)
Ígbà ìhó	4701 K ​(4428 °C, ​8002 °F)
Kíki (near r.t.)	22.56 g/cm3
when liquid (at m.p.)	19 g/cm3
Heat of fusion	41.12 kJ/mol
Heat of	563 kJ/mol
Molar heat capacity	25.10 J/(mol·K)
pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 2713 2957 3252 3614 4069 4659
Atomic properties
Oxidation states	−3, −1, 0, +1, +2, +3, +4, +5, +6, +7, +8, +9
Electronegativity	Pauling scale: 2.20
Atomic radius	empirical: 136 pm
Covalent radius	141±6 pm
Spectral lines of iridium
Other properties
Natural occurrence	primordial
Crystal structure	​(fcc)
Speed of sound thin rod	4825 m/s (at 20 °C)
Thermal expansion	6.4 µm/(m·K)
Thermal conductivity	147 W/(m·K)
Electrical resistivity	47.1 n Ω·m (at 20 °C)
Magnetic ordering	paramagnetic
Young's modulus	528 GPa
Shear modulus	210 GPa
Bulk modulus	320 GPa
Poisson ratio	0.26
Mohs hardness	6.5
Vickers hardness	1760 MPa
Brinell hardness	1670 MPa
CAS Number	7439-88-5
Main isotopes of iridium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct 188Ir syn 1.73 d ε 1.64 188Os 189Ir syn 13.2 d ε 0.532 189Os 190Ir syn 11.8 d ε 2.000 190Os 191Ir 37.3% 191Ir is stable with 114 neutrons 192Ir syn 73.827 d β- 1.460 192Pt ε 1.046 192Os 192m2Ir syn 241 y IT 0.161 192Ir 193Ir 62.7% 193Ir is stable with 116 neutrons 193mIr syn 10.5 d IT 0.080 193Ir 194Ir syn 19.3 h β- 2.247 194Pt 194m2Ir syn 171 d IT ? 194Ir