What are the physical properties of argon?
Argon is a colorless, inert gas that is found in the atmosphere in small concentration, about 0.934% by volume. Its physical properties are as follows:
Density: 0.001784 g/ml
Boiling point: 87.30 K = -185.85°C
Melting point: 83.80 K = -189.35°C
Atomic mass: 39.948 g/ml
Specific heat: 0.52 J/g-K
Heat of fusion: 1.18 kJ/mol
Heat of vaporization: 6.43 kJ/mol
Argon is used for applications in which its chemical inertness is important, such as in incandescent light bulbs to prevent the rapid corrosion of the tungsten filament and in arc welding and plasma cutting as a shield gas to prevent contact of metal with the surrounding atmosphere. It is also used between the panes of double pane windows for thermal isolation. Argon can be used in the controlled atmosphere storage of fruit and vegetables because it is relatively soluble in water so it can be absorbed into the product and slow down chemical reactions that lead to spoilage.