Question

Why is helium used in diving apparatus?

Answer 1

Helium in diving apparatus

Air contains a large amount of nitrogen and the solubility of gases in liquids increases with increase in pressure according to Henry’s law.

When sea divers dive deep into the sea, large amount of nitrogen dissolves in their blood. When they come back to the surface, solubility of nitrogen decreases, and it separates from the blood and forms small air bubbles. This leads to a dangerous medical condition called bends.

Therefore, air in oxygen cylinders used for diving is mixed with helium gas. This is done because helium is less soluble in blood than nitrogen.