Water Cycle: Formation of Cloud @ Cradle Mountain

Common Primary 5 Science Question

Lee Xian sets up an experiment as shown below. She heated some stones to 150°C and placed them in the glass bottle as shown in the set up below.

After several minutes, she observed water droplets formed on the inside surface of the glass bottle.

(a) Explain how are water droplets formed. (2m)

The tap water gains heat from the stones and evaporates to become warmer water vapour which loses heat and condenses onto cooler inner surface of the bottle, forming water droplets.

(b) What would Lee Xian observe if she changed the hot stones to ice cubes? Explain why. (2m)

She would still observe water droplets but at the outer surface of the bottle.

The warmer water vapour in the air lost heat and condensed onto cooler outer surface of the bottle, forming water droplets.