Iridium
77
Ir
Groep
9
Periode
6
Blok
d
Protonen
Elektronen
Neutronen
77
77
115
Algemene Eigenschappen
Atoomnummer
77
Atomair gewicht
192,217
Massa Getal
192
Categorie
Overgangsmetalen
Kleur
Zilver
Radioactief
Nee
From the Latin word iris meaning rainbow
Kristalstructuur
Zijvlak-gecentreerde Kubus
Historie
Iridium was discovered in 1803 by English chemist Smithson Tennant in London.
Chemists who studied platinum dissolved it in aqua regia to create soluble salts and observed a small amount of a dark, insoluble residue.
Smithson Tennant analyzed the insoluble residue and concluded that it must contain a new metal.
Chemists who studied platinum dissolved it in aqua regia to create soluble salts and observed a small amount of a dark, insoluble residue.
Smithson Tennant analyzed the insoluble residue and concluded that it must contain a new metal.
Eletronen per schil
2, 8, 18, 32, 15, 2
Electronconfiguratie
[Xe] 4f14 5d7 6s2
Iridium is the most corrosion-resistant metal known
Fysieke Eigenschappen
Fase
Vast
Dichtheid
22,56 g/cm3
Smeltpunt
2739,15 K | 2466 °C | 4470,8 °F
Kookpunt
4701,15 K | 4428 °C | 8002,4 °F
Fusiewarmte
26 kJ/mol
Verdampingswarmte
560 kJ/mol
Specifieke Warmtecapaciteit
0,131 J/g·K
Overvloedig aanwezig in de aardkorst
4×10-8%
Overvloedig aanwezig in het universum
2×10-7%
CAS-nummer
7439-88-5
PubChem CID nummer
23924
Atoomeigenschappen
Atoomstraal
136 pm
Covalentiestraal
141 pm
Electronegativiteit
2,2 (Pauling schaal)
Ionisatiepotentiaal
8,967 eV
Atoomvolume
8,54 cm3/mol
Thermische geleiding
1,47 W/cm·K
Oxidatietoestanden
-3, -1, 1, 2, 3, 4, 5, 6, 7, 8, 9
Toepassingen
Iridium is used in making crucibles and other equipment that is used at high temperatures.
Iridium is also used as a hardening agent in platinum alloys.
Its resistance to arc erosion makes iridium alloys ideal for electrical contacts for spark plugs.
Radioactive isotopes of iridium are used in radiation therapy for the treatment of cancer.
Iridium is also used as a hardening agent in platinum alloys.
Its resistance to arc erosion makes iridium alloys ideal for electrical contacts for spark plugs.
Radioactive isotopes of iridium are used in radiation therapy for the treatment of cancer.
Iridium is considered to be of low toxicity
Isotopen
Stabiele isotopen
191Ir, 193IrInstabiele isotopen
164Ir, 165Ir, 166Ir, 167Ir, 168Ir, 169Ir, 170Ir, 171Ir, 172Ir, 173Ir, 174Ir, 175Ir, 176Ir, 177Ir, 178Ir, 179Ir, 180Ir, 181Ir, 182Ir, 183Ir, 184Ir, 185Ir, 186Ir, 187Ir, 188Ir, 189Ir, 190Ir, 192Ir, 194Ir, 195Ir, 196Ir, 197Ir, 198Ir, 199Ir