Candle In A Jar

Kinetic Particle Theory
Candle in a Jar Experiment


Purpose: To observe properties of a phenomenon and explain what is happening Kinetic Particle Theory.


Instruments:
Glass Jar
Petri Dish
Matchsticks/Lighter
Water
Candle
Ball of Clay

Steps:

1. Pour some water into the petri dish.
2. Push the candle into the ball of clay so that it stays upright.
3. Light the candle with a matchstick/lighter.
4. Invert the glass jar and place it over the candle..
5. Observe.




Explanation:

The flame on the candle needs the gas oxygen to keep burning. Once we place the glass container over the lit candle, the oxygen inside begins to get used up. Once all the oxygen has been used, the flame will go out. However, there are still other gases remaining inside the glass (nitrogen, argon, carbon dioxide, etc). But these gases have lower pressure inside the glass when compared to the higher atmospheric pressure on the outside of the glass. This higher atmospheric pressure from the outside pushes the water from the plate up and into the glass.

One more thing is happening here to make the water rise into the glass. When we cover the lit candle with the glass, it heats the air inside the glass. The heated air expands. As it expands it comes out from under the glass container. You might observe some bubbles after you put the glass over the candle. Thats the hot air escaping. Once the flame dies out, the air inside the glass begins to cool down. As it cools, the air contracts inside the glass container. This contraction pulls the water from outside on the plate into the glass.

According to the Kinetic Particle Theory, all molecules are in constant random motion. In this case, the air particles inside the glass jar. As oxygen is being used up by the burning candle, the other gases that remain, such as carbon dioxide and nitrogen etc have a lower pressure as compared to the atmospheric pressure outside the jar. The molecules of air outside the jar move into the jar due to the difference in pressure. This shows the kinetic particle theory in action while conducting this experiment. <<< stating a theory