Materials Required 1 bottle Warm Water Match stick How to do it Pour enough warm water into the bottle to cover the bottom of the container. Light the match stick and place the match head inside the bottle. Now allow the bottle to fill with smoke. Close the bottle tightly with a cap. Squeeze the bottle hard 5-6 times. When you release the bottle, ask your child to see the formation of cloud. It may disappear between 'squeezes'. Explanation Molecules of water vapour will bounce around like molecules of other gases unless you give them a reason to stick together. Cooling the vapour slows the molecules down, so they have less kinetic energy and more time to interact with each other. When you squeeze the bottle, you compress the gas and increase its temperature. Releasing the container lets the gas expand, which causes its temperature to go down. Expansion make the gas cooler. Real clouds form as warm air rises. As air gets higher, its pressure is reduced. The air expands, which causes it to cool. As it cools below the dew point, water vapour forms the lets which we see as clouds. Smoke acts the same in the atmosphere as it does in the bottle.
How to do it
Explanation