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77Ir

Element 77

Iridium

Transition metals

Iridium is a chemical element with symbol Ir and atomic number 77.

Key data

Atomic number
77
Atomic mass
192.217 u
Group / Period
9 / 6
Block
d-block
Phase at STP
Solid
Density
22.56 g/cm³
Melting point
2445.8 °C
Boiling point
4129.9 °C
Electron configuration
[Xe] 4f14 5d7 6s2

Common uses

  • Spark plugs
  • Crucibles
  • Asteroid impact marker

Discovery

Year: 1803

Discovered by: Smithson Tennant

Frequently asked questions

What is the atomic number of Iridium?

Iridium has atomic number 77. Its symbol is Ir and its atomic mass is 192.217 u.

What category of element is Iridium?

Iridium is classified as transition metals. It sits in group 9, period 6 of the periodic table.

What is Iridium used for?

Common uses of Iridium include: Spark plugs, Crucibles, Asteroid impact marker.

When was Iridium discovered?

Iridium was discovered in 1803 by Smithson Tennant.

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