Iridium (Ir) – Periodic Table [Element Information & More]

iridium element periodic table

Iridium element (Ir) is in group 9 and period 6 of a periodic table. Iridium is in the d-block and it is classified as a transition element on the periodic table.

There is a lot more information related to iridium which is mentioned in the Information Table given below.

So let’s dive right into it!

Table of contents

Iridium Element (Information Table)

The important data related to iridium element is given in the table below.

Appearance of iridiumSilvery white metallic surface
Atomic number of iridium77
Symbol of iridiumIr
Atomic mass of iridium192.22 u
Protons, Neutrons & Electrons in iridiumProtons: 77, Neutrons: 115, Electrons: 77
State of iridium (at STP)Solid
Group number of iridium in periodic table9
Period number of iridium in periodic table6
Block of iridium in periodic tabled-block
Category of iridiumTransition metals
Bohr model or Electrons per shell or Electrons arrangement in iridium2, 8, 18, 32, 15, 2
Electron configuration of iridium[Xe] 4f14 5d7 6s2
Orbital diagram of iridiumorbital diagram of iridium
Electronegativity of iridium (on pauling scale)2.2
Atomic radius of iridium (van der Waals radius)202 picometers
Density of iridium22.56 g/cm3
1st ionization energy of iridium9.1 eV
Main isotope of iridium193Ir
Melting point of iridium2719 K or 2446 °C or 4435 °F
Boiling point of iridium4403 K or 4130 °C or 7466 °F
Crystal structure of iridiumFace Centered Cubic (FCC)
Discovery of iridiumBy Smithson Tennant in 1803

Also see: Interactive Periodic Table (It has rotating bohr models as well as many other details of all the 118 elements in a single periodic table).

Iridium element in Periodic table

The Iridium element (Ir) has the atomic number 77 and is located in group 9 and period 6. Iridium is a metal and it is classified as a transition element.

Click on above elements in the periodic table to see their information.

Facts about iridium

Here are a few interesting facts about the iridium element.

  1. Smithson Tennant was the chemist who discovered the iridium element in the year 1803.
  2. Iridium was given its name from the Latin word “Iris”, meaning rainbow.
  3. Iridium is the 2nd most dense element after osmium.
  4. Machining of iridium metal is very difficult as it is very hard.
  5. The concentration of iridium in the earth’s crust is only 0.4 parts per billion, which is very rare.

Properties of iridium

Here is a list of some physical properties and chemical properties of iridium.

Physical properties of iridium

  • Iridium has a silvery white metallic appearance.
  • Iridium has FCC crystal structure.
  • Iridium has many isotopes, and the most abundant isotope is 193Ir.
  • Iridium has a density of 22.56 g/cm3 and its atomic mass is 192.22 amu.
  • The melting point and boiling point of iridium is 2719 K and 4403 K respectively.

Chemical properties of iridium

  • Iridium is unreactive to most of the acids.
  • Iridium reacts with the atmospheric oxygen at higher temperatures.
  • Iridium reacts with sulfur to give iridium disulfide.
  • Iridium reacts with salts like NaCl and NaCN.

Uses of iridium

Here are some uses of the iridium element.

  • Iridium is mostly used as an alloying element with other metals to make them hard.
  • Iridium is also used in crucible  furnaces because it can resist high temperatures..
  • Iridium is also used in making electrical contacts as well as fountain pen tips.
  • The platinum-iridium alloy was used to make the international standard kilogram weight. (it contains 10% iridium and 90% platinum).
  • Iridium is also used in crucible  furnaces because it can resist high temperatures.

External resources:

  1. Iridium – Wikipedia. (2023, January 1). Iridium – Wikipedia.
  2. Iridium – Element information, properties and uses | Periodic Table. (n.d.). Iridium – Element Information, Properties and Uses | Periodic Table.
  3. P. (n.d.). Iridium | Ir (Element) – PubChem. Iridium | Ir (Element) – PubChem.
  4. It’s Elemental – The Element Iridium. (n.d.). It’s Elemental – the Element Iridium.
  5. Periodic Table of Elements: Los Alamos National Laboratory. (n.d.). Periodic Table of Elements: Los Alamos National Laboratory.
  6. Atomic Weight of Iridium | Commission on Isotopic Abundances and Atomic Weights. (n.d.). Atomic Weight of Iridium | Commission on Isotopic Abundances and Atomic Weights.
  7. Atomic Data for Iridium (Ir). (n.d.). Atomic Data for Iridium (Ir).
  8. Iridium | Ir | ChemSpider. (n.d.). Iridium | Ir | ChemSpider.
  10. Possolo, et al. (2018, January 4). Interpreting and propagating the uncertainty of the standard atomic weights (IUPAC Technical Report). Pure and Applied Chemistry, 90(2), 395–424.
  11. Emsley, J. (2011). Nature’s Building Blocks: An A-Z Guide to the Elements. United Kingdom: OUP Oxford.
  12. Haynes, W. M. (Ed.). (2014, June 4). CRC Handbook of Chemistry and Physics.
  13. Electronic structure of the elements. (2000, March). The European Physical Journal C, 15(1–4), 78–79.
  14. James A. M. & Lord M. P. (1992). Macmillan’s chemical and physical data. Macmillan.
  15. Bedford, et al. (1996, April 1). Recommended values of temperature on the International Temperature Scale of 1990 for a selected set of secondary reference points. Metrologia, 33(2), 133–154.
  16. Allred, A. (1961, June). Electronegativity values from thermochemical data. Journal of Inorganic and Nuclear Chemistry, 17(3–4), 215–221.

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