How will you show that air is dissolved in water

We can show that air is dissolved in water by gently heating water and observing air bubbles coming out before it boils.

Materials Required

• A beaker of water
• A tripod stand and burner (or stove)
• Thermometer (optional)

Procedure

1. Take some clean water in a beaker.
2. Slowly heat the water without bringing it to a boil.
3. Observe small bubbles forming on the inner surface of the beaker.

Observation

Before the water starts boiling, tiny air bubbles appear and rise to the surface. These bubbles are not due to boiling but are air molecules escaping from the water as temperature increases.