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

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)
• Iridium element in Periodic table
• Facts about Iridium
• Properties of Iridium
• Uses of Iridium

Iridium Element (Information Table)

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

Appearance of iridium	Silvery white metallic surface
Atomic number of iridium	77
Symbol of iridium	Ir
Atomic mass of iridium	192.22 u
Protons, Neutrons & Electrons in iridium	Protons: 77, Neutrons: 115, Electrons: 77
State of iridium (at STP)	Solid
Group number of iridium in periodic table	9
Period number of iridium in periodic table	6
Block of iridium in periodic table	d-block
Category of iridium	Transition metals
Bohr model or Electrons per shell or Electrons arrangement in iridium	2, 8, 18, 32, 15, 2
Electron configuration of iridium	[Xe] 4f14 5d7 6s2
Orbital diagram of iridium
Electronegativity of iridium (on pauling scale)	2.2
Atomic radius of iridium (van der Waals radius)	202 picometers
Density of iridium	22.56 g/cm3
1st ionization energy of iridium	9.1 eV
Main isotope of iridium	193Ir
Melting point of iridium	2719 K or 2446 °C or 4435 °F
Boiling point of iridium	4403 K or 4130 °C or 7466 °F
Crystal structure of iridium	Face Centered Cubic (FCC)
Discovery of iridium	By 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 2^nd 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. https://en.wikipedia.org/wiki/Iridium
2. Iridium – Element information, properties and uses | Periodic Table. (n.d.). Iridium – Element Information, Properties and Uses | Periodic Table. https://www.rsc.org/periodic-table/element/77/iridium
3. P. (n.d.). Iridium | Ir (Element) – PubChem. Iridium | Ir (Element) – PubChem. https://pubchem.ncbi.nlm.nih.gov/element/Iridium
4. It’s Elemental – The Element Iridium. (n.d.). It’s Elemental – the Element Iridium. https://education.jlab.org/itselemental/ele077.html
5. Periodic Table of Elements: Los Alamos National Laboratory. (n.d.). Periodic Table of Elements: Los Alamos National Laboratory. https://periodic.lanl.gov/77.shtml
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. https://ciaaw.org/iridium.htm
7. Atomic Data for Iridium (Ir). (n.d.). Atomic Data for Iridium (Ir). https://physics.nist.gov/PhysRefData/Handbook/Tables/iridiumtable1.htm
8. Iridium | Ir | ChemSpider. (n.d.). Iridium | Ir | ChemSpider. http://www.chemspider.com/Chemical-Structure.22367.html?rid=78abd960-e271-406c-9695-710e4b757ac2
9. C&EN: IT’S ELEMENTAL: THE PERIODIC TABLE – IRIDIUM. (n.d.). C&EN: IT’S ELEMENTAL: THE PERIODIC TABLE – IRIDIUM. https://pubsapp.acs.org/cen/80th/iridium.html?
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. https://doi.org/10.1515/pac-2016-0402
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. https://doi.org/10.1201/b17118
13. Electronic structure of the elements. (2000, March). The European Physical Journal C, 15(1–4), 78–79. https://doi.org/10.1007/bf02683401
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. https://doi.org/10.1088/0026-1394/33/2/3
16. Allred, A. (1961, June). Electronegativity values from thermochemical data. Journal of Inorganic and Nuclear Chemistry, 17(3–4), 215–221. https://doi.org/10.1016/0022-1902(61)80142-5