Иридиум

77
Ir
Група
9
Периода
6
блок
d
Protons
Electrons
Neutrons
77
77
115
Општи Својства
Атомски број
77
Атомска тежина
192,217
Mass Number
192
Category
Преоден метал
Color
Silver
Radioactive
Не
From the Latin word iris meaning rainbow
Кристална структура
Face Centered Cubic
History
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.
Electrons per shell
2, 8, 18, 32, 15, 2
Електронска конфигурација
[Xe] 4f14 5d7 6s2
Ir
Iridium is the most corrosion-resistant metal known
Физички Својства
Фаза
Solid
Густина
22,56 g/cm3
Точка на топење
2739,15 K | 2466 °C | 4470,8 °F
Точка на вриење
4701,15 K | 4428 °C | 8002,4 °F
Топлина на топење
26 kJ/mol
Топлина на испарување
560 kJ/mol
Specific Heat Capacity
0,131 J/g·K
Abundance in Earth's crust
4×10-8%
Abundance in Universe
2×10-7%
Pieces
Кредити на слика: Images-of-elements
Pieces of pure iridium
CAS Number
7439-88-5
PubChem CID Number
23924
Атомски Својства
Атомски полупречник
136 pm
Ковалентен полупречник
141 pm
Електронегативност
2,2 (Полингова скала)
Ionization Potential
8,967 eV
Atomic Volume
8,54 cm3/mol
Thermal Conductivity
1,47 W/cm·K
Oxidation States
-3, -1, 1, 2, 3, 4, 5, 6, 7, 8, 9
Applications
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 considered to be of low toxicity
Isotopes
Stable Isotopes
191Ir, 193Ir
Unstable Isotopes
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