With Activity 3, show a demonstration for precipitation. Cover it tightly with the lid and let it stand 2 minutes. Place the large lid, with holes punctured in it, on top of the jar. Cover the lid with ice cubes and let it stand 3 minutes. Remove the lid and cubes.
Sprinkle chalk dust into the jar.
Cover the jar with the tightly fitting lid. After 2 minutes observe the inside of the jar. A cloud has formed along with precipitation falling. By heating and cooling the water in the jar, it caused droplets of water to form. This demonstration shows that clouds are collections of tiny water droplets that form around particles of dust, dirt or salt.