The name "argon" is derived from the Greek word meaning "lazy" or "inactive", as a reference to the fact that the element undergoes almost no chemical reactions.The complete octet (eight electrons) in the outer atomic shell makes argon stable and resistant to bonding with other elements.was suspected to be a component of air by Henry Cavendish in 1785.
Its triple point temperature of 83.8058 K is a defining fixed point in the International Temperature Scale of 1990.
Argon is produced industrially by the fractional distillation of liquid air.
Henry Moseley later solved this problem by showing that the periodic table is actually arranged in order of atomic number. Argon's complete octet of electrons indicates full s and p subshells.
This full outer energy level makes argon very stable and extremely resistant to bonding with other elements.
Argon is mostly used as an inert shielding gas in welding and other high-temperature industrial processes where ordinarily unreactive substances become reactive; for example, an argon atmosphere is used in graphite electric furnaces to prevent the graphite from burning. Argon has approximately the same solubility in water as oxygen, and is 2.5 times more soluble in water than nitrogen.
Argon is also used in incandescent, fluorescent lighting, and other gas discharge tubes. Argon is colorless, odorless, nonflammable and nontoxic as a solid, liquid, and gas.
Argon fluorohydride (HAr F), a compound of argon with fluorine and hydrogen that is stable below 17 K, has been demonstrated.
Lord Rayleigh's method for the isolation of argon, based on an experiment of Henry Cavendish's.
The gases are contained in a test-tube (A) standing over a large quantity of weak alkali (B), and the current is conveyed in wires insulated by U-shaped glass tubes (CC) passing through the liquid and round the mouth of the test-tube.