77 Ir Iridium 192.22 u

Iridium

Period
6
Group
9
Block
d-block
Phase (STP)
Solid

Iridium is the most corrosion-resistant metal known. It is used in spark plugs, crucibles, and the international prototype kilogram.

About Iridium

Iridium (Ir) is the most corrosion-resistant metal known, resisting acids and remaining stable at high temperatures. Element 77 occupies group 9 of period 6 in the d-block, with an atomic mass of 192.22, the electron configuration [Xe] 4f¹⁴ 5d⁷ 6s², and a Pauling electronegativity of 2.2. This durability suits it to hard-wearing applications such as long-life spark-plug electrodes and crucibles for growing high-purity crystals. Iridium historically defined the standard for permanence: the international prototype kilogram was a platinum-iridium alloy. A dense, hard, silvery member of the platinum group, it is solid at standard conditions.

Physical Properties

Atomic Mass 192.22 u
Phase at STP Solid

Electronic Properties

Electronegativity 2.2

Electron Configuration

Configuration [Xe] 4f¹⁴ 5d⁷ 6s²

Electron Shell Configuration

Iridium electron shell configuration Ir 2e⁻ 8e⁻ 18e⁻ 32e⁻ 15e⁻ 2e⁻
Electron shell structure of Iridium — electrons per shell.
Shell Electrons
1 (K) 2
2 (L) 8
3 (M) 18
4 (N) 32
5 (O) 15
6 (P) 2

Position in Periodic Table

Iridium position in the periodic table Ir

Block & Period

Block

s p d f

Period

1 2 3 4 5 6 7

Periodic Table

Lanthanides Actinides

More Transition Metal

21 Sc Scandium 22 Ti Titanium 23 V Vanadium 24 Cr Chromium 25 Mn Manganese 26 Fe Iron 27 Co Cobalt 28 Ni Nickel 29 Cu Copper 30 Zn Zinc

Frequently Asked Questions

What is Iridium?
Iridium (Ir) is a chemical element with atomic number 77. It is a solid at standard temperature and pressure, classified as a transition metal.
What are the key properties of Iridium?
Iridium has an atomic mass of 192.22 u.
What is the electron configuration of Iridium?
The electron configuration of Iridium is [Xe] 4f14 5d7 6s2. It is in the d-block of the periodic table.
What is the electronegativity of Iridium?
Iridium has an electronegativity of 2.2 on the Pauling scale.