Why ishelium used in diving apparatus?
Aircontains a large amount of nitrogen and thesolubility of gases in liquids increases with increase in pressure.When sea divers dive deep into the sea, large amount of nitrogendissolves in their blood. When they come back to the surface,solubility of nitrogen decreases and it separates from the blood andforms small air bubbles. This leads to a dangerous medical conditioncalled bends. Therefore, air in oxygen cylinders used for diving isdiluted with helium gas. This is done as He is sparingly less solublein blood.