Candle Experiment PDF

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Candle Experiment chem 217...

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Candle Experiment

Purpose: To be introduced in how to conduct experiments by observing how a flame can be reignited by its’ smoke, as well as how the flame interacts with its surroundings. Also to understand the chemical reaction that causes this: wax + O 2 → H 2 O (g) +C O 2 ( g) +heat + light Procedure (From Chemistry Home Lab Manual pp. 52-55): Part A: 1. Light a candle and let it burn for about one minute. 2. Have a lighted match or lighter ready. 3. Carefully blow out the candle. 4. Watch the smoke trail coming up from the extinguished candle and quickly place your lighted match into that smoke stream. 5. The candle should re-ignite.

Part B: 1. With a few drops of hot wax fix your candle to the center of a bowl. 2. Pour water into the bowl so that it is partially filled. 3. Light the candle. 4. Place an empty jar or glass over the candle so that the edge is under the water line (see Figure CE.2). 5. The candle should extinguish.

Part C: 1. Mold and cut a square of aluminum foil into the shape shown in Figure CE.3. 2. Place the foil between the candle and flame so that the wick goes through the slit in the foil. Candle Experiment 3. The candle should extinguish (the slit may have to be narrowed manually).

Part D:

1. Place several ice cubes into a large square of aluminum foil. 2. Pull together the corners to form a sack filled with ice. 3. Hold this sack over (about 20 cm) a burning candle. 4. Water droplets should form on the outside of the aluminum sack.

Part E: 1. Fix a candle in a glass jar and light it. 2. In the other glass jar add two tablespoons of baking soda. 3. Then add about 1/5 cup of vinegar to the baking soda. 4. The baking soda will foam. 5. Quickly tip the foaming glass and “pour” the carbon dioxide formed into the jar with the burning candle. Note: Be careful not to tip the wet vinegar/baking soda mixture into the candle jar. 6. The candle should extinguish.

Observations/ Results:

Experiment Part A

Part B

Part C

Part D

Observations Results and Explanations The candle was lit then blown The candle was relit due to out, creating a smoke trail. the wax vapor in the smoke When the flame was brought trail creating a path back to to this smoke trail, the candle the wick of the candle. was relit. The candle was lit, then a cup the flame extinguished due to was places on the flame. The lack of oxygen. There is a flame remained lit. The water change of pressure inside the then rose and the flame cup, causing a difference extinguished. between the pressure inside the cup and the atmospheric pressure outside the cup. The candle was lit, then aluminum foil was placed on top of the flame. The flame extinguished. The candle was lit, ice was

The foil cause the wax to not be able to melt, thus giving the flame no fuel to burn through. The water produced from the

Part E

placed in the aluminum foil and then both were put on top of the flame. The aluminum foil became wet, and the flame extinguished. The candle was lit, baking soda and vinegar was combined. When this mixture was poured onto the flame, the flame extinguished.

combustion reaction condensates on the foil, causing the extinguishing of the candle. The baking soda and vinegar creates C O2 . Since the mixture is then denser than air, it flows over the candle, extinguishing it from lack of oxygen.

Answers to Questions: 1. When the flame extinguished, it left a smoke trail of wax vapor leading back to the wick. When a flame is then brought to this smoke trail, the flame follows the path back to the wick and reignites. 2. A) The aluminum foil blocked the wax from the flame, causing the oxygen to not be able to reach the flame, thus the flame extinguished from lack of oxygen. B) Any way to limit the oxygen to the flame will eventually extinguish it. For example, putting a balloon around the candle will eventually extinguish it once it has used up all of the oxygen in the balloon. C) CaCO 3 ( s ) +2 HCl ( aq ) → CaCl 2 ( aq ) +H 2O ( l )+ CO 2(g) 3. When the foil is placed above the flame, the water molecules condensate due to the heating, causing a change of state from liquid to gas. This proves that candles are hydrocarbons as the candle’s products are water and carbon dioxide. 4. A) When the oxygen in the jar is used up, the pressure inside the jar decreases, creating a vacuum-like effect, and sucking the water into it. B) Due to the pressure change inside the jar, the jar will continue to suck up water until the pressure inside and outside the jar are even. It is the same reason that in a sinking car, you will not be able to open the doors until the pressure is the same in the car as it is in the water. 5. In the normal candle, the flame is simply using the available oxygen around it to burn. The shape is caused by the heat of the flame and the coldness of the air. Gravity also plays a roll in keeping the flame oval shaped as well. In the micro gravity candle, a sphere is formed due to the equal distribution of the oxygen particles (ie the flame has no gravity to shape it, so the spherical shape is the most symmetric).

Conclusion:

In conclusion, this experiment shows that reactants in a chemical equation can be altered in many ways, causing vastly different products to be made, or even the prevention of the reaction as a whole. This experiment also shows that in a given environment, if a reaction is going to happen, it will use up all of the available reactants in that environment until it runs out of at least one of the reactants....