Argon atom

Argon is basically a Greek word, argos meaning lazy. It was suspected in 1785 that it was present in air by Henry Cavendish. Later it was discovered by Lord Rayleigh and Sir William Ramsay in 1894.

Introduction :
The Argon atom is the chemical element which is present in the eighteenth group of the periodic table. Argon atom symbol is Ar. It is having an atomic number 18 and atomic weight 39.948amu it’s equal to 40 amu. It belongs to eighteenth group, (viii A) period and it is a p-block element. It has 18 electrons and 18 protons and has 22 neutrons. Density of Argon atom is 1.784 kg/m^3. Argon atom belongs to noble gas series. It belongs to p–block is predicted by its electronic configuration. The electronic configuration is based on atomic number of an atom, so the electronic configuration of Argon atom is 1s² 2s² 2p⁶ o [Ne] 3s² 3p⁶, here the outermost electron present in the p-orbital so it belongs to p-block. It has cubic face centered crystal structure. It is diamagnetic in nature. It is the third noble gas.

Electron Shell model of Argon atom

It has 3 main isotopes; they are Ar-40, Ar-36, and Ar-38. Ar -39 is made by cosmic ray activity. Ar-40 is produced by neutron capture method from K -39 and also by alpha emission by calcium and Ar-37 is produced by the decay of Ca -40.

Physical properties of argon atom:

1. It is a non-metallic, colorless and odorless  gas at room temperature i.e. at 298K.
2. Its melting point and boiling point are 83.8K and 87.3K respectively.
3. It occupies about 1% of Earth’s atmosphere.
4. It is chemically inert so it does not react with any element or a molecule.
5. It is stored at high pressures.

Applications of argon atom:

Argon atom is used

1.     In  lighting due to its high stability AND it will not react with the filament in a bulb even under high temperatures

2.     Due to its inertness, it is used as inert gas shield in case of welding.

3.      In the manufacture of titanium as a non- reactive blanket and many more.