Iridium | Chemistry

Seaway District High School, Iroquois, Ontario, Canada

Iridium, 77, Seaway District High School, Iroquois ON

Iridium: The name iridium comes from the Greek word for rainbows due to the diverse colours of iridium salts. Iridium is one of the rarest elements in the Earth’s crust. Because it resists corrosion at high temperatures, it can be used in high temperature applications such as crucibles and spark plugs. When alloyed with osmium it has been used for pen tips and compass bearings. This is our play on the search for the pot of gold at the end of the rainbow — we are “looking for a crucible of iridium at the end of the rainbow”.

Original artwork by Taylor Houghton. Teacher: Melissa Ringler, Seaway District High School, Iroquois, Ontario, Canada

Atomic properties*

Name:

Iridium

Symbol:

Ir

Atomic number:

77

Atomic mass:

192.22 amu

Melting point:

2446°C

Boiling point:

4428°C

Density:

22.56 g/cm³

Electronegativity:

2.2

# of Isotopes:

2

State:

Solid

Colour:

White (slight yellow cast)

Classification:

Metallic**

* Haynes, W. M. (2011). CRC Handbook of Chemistry and Physics, 91st edition: http://www.hbcponline.com/ Retrieved April 7, 2011

** Winter, M. (2010). Home of the Periodic Table. Retrieved April 8, 2011, from Web Elements: http://www.webelements.com/