Argon (Ar) – Periodic Table [Element Information & More]

Argon element (Ar) is in group 18 and period 3 of a periodic table. Argon is in the p-block and it is classified as a noble gas element on the periodic table.

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

So let’s dive right into it!

Table of contents

• Argon element (Information Table)
• Argon element in Periodic table
• Facts about Argon
• Properties of Argon
• Uses of Argon

Argon Element (Information Table)

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

Appearance of argon	Colorless gas
Atomic number of argon	18
Symbol of argon	Ag
Atomic mass of argon	39.95 u
Protons, Neutrons & Electrons in argon	Protons: 18, Neutrons: 22, Electrons: 18
State of argon (at STP)	Gas
Group number of argon in periodic table	18
Period number of argon in periodic table	3
Block of argon in periodic table	p-block
Category of argon	Noble gas
Bohr model or Electrons per shell or Electrons arrangement in argon	2, 8, 8
Electron configuration of argon	[Ne] 3s2 3p6
Orbital diagram of argon
Valence electrons in argon	8
Atomic radius of argon (van der Waals radius)	188 picometers
Density of argon	1.79 g/L
1st ionization energy of argon	15.76 eV
Main isotope of argon	40Ar
Melting point of argon	83.81 K or -189.34 °C or -308.81 °F
Boiling point of argon	87.3 K or -185.84 °C or -302.52 °F
Crystal structure of argon	Face Centered Cubic (FCC)
Discovery of argon	By Lord Rayleigh and William Ramsay (in 1894)

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).

Argon element in Periodic table

The Argon element (Ar) has the atomic number 18 and is located in group 18 and period 3. Argon is a nonmetal and it is classified as a noble gas element.

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

Facts about argon

Here are a few interesting facts about argon element.

1. The name “Argon” came from the Greek word “argos”, which means inactive.
2. Initially the symbol of argon element was “A”, but it was changed to “Ar” by IUPAC in 1957.
3. Argon is only 0.94% by volume in the earth’s atmosphere.
4. Argon is the 3^rd most abundant element present in the earth’s atmosphere.
5. On the earth, the argon gas is prepared by the radioactive decay of potassium.
6. Argon was the first noble gas to be discovered. Other noble gases were discovered after the discovery of argon gas.
7. Argon remains closer to the earth’s surface, because it is denser than air.

Properties of argon

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

Physical properties of argon

• Argon is a colorless, odorless and tasteless gas.
• The argon gas glows with a violet light when it is ionized.
• Argon gas is 38% more denser than air.
• The melting point and boiling point of argon is -189.34 °C and -185.84 °C respectively.
• There are many isotopes of argon, but the most abundant isotope is ⁴⁰Ar (which has an abundance of 99.6%).

Chemical properties of argon

• Argon is an inert gas and so it does not show any reaction with other elements.
• It has been found that the argon forms argon fluorohydride at the temperature below -256.15 °C.

Uses of argon

Here are some uses of the argon element.

• Argon is used as a shielding gas during various welding processes.
• Argon gas is used to preserve important historical documents, maps, etc. The argon gas prevents the paper or ink from degradation.
• Argon is inert gas and it cannot transfer heat through it. Because of this reason it is filled in double glazed windows between the two panes. This acts like thermal insulation.
• Argon is also used to store some chemicals which are very reactive to the atmospheric air.
• Argon is used in incandescent bulbs to prevent the filament from oxidation.
• Argon is also filled on the top of the wine bottles which prevents the contact of wine from oxygen.

External resources:

1. Periodic Table of Elements: Los Alamos National Laboratory. (n.d.). Periodic Table of Elements: Los Alamos National Laboratory. https://periodic.lanl.gov/18.shtml
2. It’s Elemental – The Element Argon. (n.d.). It’s Elemental – the Element Argon. https://education.jlab.org/itselemental/ele018.html
3. Atomic Data for Argon (Ar). (n.d.). Atomic Data for Argon (Ar). https://physics.nist.gov/PhysRefData/Handbook/Tables/argontable1.htm
4. C&EN: IT’S ELEMENTAL: THE PERIODIC TABLE – THE NOBLE GASES. (n.d.). C&EN: IT’S ELEMENTAL: THE PERIODIC TABLE – THE NOBLE GASES. https://pubsapp.acs.org/cen/80th/noblegases.html?
5. Haynes, W. M. (Ed.). (2014, June 4). CRC Handbook of Chemistry and Physics. https://doi.org/10.1201/b17118
6. Emsley, J. (2011). Nature’s Building Blocks: An A-Z Guide to the Elements. United Kingdom: OUP Oxford.
7. 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
8. Kaye, G W.C., & Laby, T H. Tables of physical and chemical constants. 15th Edition. United States.
9. Zhang, Y., Evans, J. R. G., & Yang, S. (2011, January 11). Corrected Values for Boiling Points and Enthalpies of Vaporization of Elements in Handbooks. Journal of Chemical & Engineering Data, 56(2), 328–337. https://doi.org/10.1021/je1011086
10. Possolo, A., van der Veen, A. M. H., Meija, J., & Hibbert, D. B. (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. Sansonetti, J. E., & Martin, W. C. (2005, December). Handbook of Basic Atomic Spectroscopic Data. Journal of Physical and Chemical Reference Data, 34(4), 1559–2259. https://doi.org/10.1063/1.1800011
12. Bondi, A. (1964, March). van der Waals Volumes and Radii. The Journal of Physical Chemistry, 68(3), 441–451. https://doi.org/10.1021/j100785a001
13. James A. M. & Lord M. P. (1992). Macmillan’s chemical and physical data. Macmillan.
14. Holden, et al. (2018, December 1). IUPAC Periodic Table of the Elements and Isotopes (IPTEI) for the Education Community (IUPAC Technical Report). Pure and Applied Chemistry, 90(12), 1833–2092. https://doi.org/10.1515/pac-2015-0703