Candle experiment PDF

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Candle Experiment Purpose: to observe several ways of extinguishing a flame and how a flame can affect its surroundings. The following 5 approaches of the candle flame. to learn laboratory skills. Also, to learn the concept of adding of subtracting properties to a reaction and examining the result. This was accomplished by determining the balanced equation for a candle wick to burn. This process can be defined by the following chemical reaction. Wax + O2 H2O + CO2+ heat + light Procedure: Part A- Reigniting a candle 1) Light the candle, let it burn for one minute. 2) Make sure to have a lighted match or lighter handy. 3) Carefully blow out the candle. 4) Observe the smoke trail coming from the extinguished candle and quickly place the lighted match or lighter on that trail. Part B- Water Suck Up 1) Use a few drops of hot wax to fix the candle into the centre of a bowl. 2) Pour water into the bowl so it is partially filled. 3) Light the candle. 4) Place an empty glass over the candle so that the edge is under the water line. 5) The candle will extinguish. Part C- Extinguishing a Candle with Aluminum Foil 1) Shape a piece of aluminum foil into a rectangle with a cut out of a thick slit in the middle. 2) Place the foil between the candle and flame so that the wick goes through the slit in the foil. 3) The candle will extinguish. Part D- Candle Condensation 1) Place several ice cubes into a large square of aluminum foil and form a sack. 2) Hold the sack over the burning candle. 3) Water droplets will form on the outside of the aluminum sack. Part E- Extinguishing a Candle with Carbon Dioxide 1) Light a candle in a glass jar. 2) In another glass jar add two tablespoons of baking soda. 3) Add 1/5 cup of vinegar to the baking soda. 4) The baking soda will foam, quickly tip the foaming glass and pour the carbon dioxide formed into the jar with the candle. 5) The candle will extinguish.

Observations and Results:

Experiment Part A- Reigniting a Candle

Observations - Combustion to blue flame occurs where match connects with wax vapor. - Flame travels down gaseous chain to the origin at the wick. - Wick is reignited

Part B- Water Suck Up

-. After the jar was placed over the candle, the flame grew momentarily, then dims and extinguished. -The water then gets sucked into the glass and rise inside the glass.

Results and Explanations - When the candle is extinguished, the wax flame turns to gaseous state creating a smoke trail originating at the wick. This trail enables the candle to be relighted as the smoke trail combines all the necessary reactants for a combustion reaction. The flame follows a chain reaction along smoke trail as the wax vapor is the fuel for the reaction. When the flame reaches the wick, the candle is reignited. - The flame uses up the oxygen in the cup creates a low pressure. Atmospheric pressure then tries to force its way in. Because the water at the base of the cup has created an air tight seal, the pressure difference between the inside and outside of the cup causes the water to raise until pressure (inside the cup) is equal to the pressure outside. This pressure change due to the reduction in the gas content inside the container

Part C- Extinguishing a Candle with Aluminum Foil

- After the aluminum foil was placed around the wick, the flame reduced, then extinguished.

- The aluminum around the wick prevents the wax further down the candle from melting as it reflects the heat. For the flame to stay, wax has to melt and travel up the wick to keep the flame. If the wax is no longer melting, the flame will run out of fuel to burn then the candle extinguished

Part D- Candle Condensation

- After placing the Aluminum filled ice sack over the candle, condensation begins, and water droplets are formed.

When aluminum sack is put over the flame, a misty effect is created, water droplets formed. Water is one of the products of the combustion reaction, so when the cold bag of aluminum is held over

the flame the produced water from combustion will be condensed on the cold surface of the foil. Part E- Extinguishing a Candle with Carbon Dioxide

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The flame is extinguished rapidly when the jar is opened over the candle.

When baking soda and vinegar interact the produce CO2. As Carbon Dioxide is a heavier substance than air, the gas will flow over the candle rather than up into the air. With Carbon Dioxide coating the flame, there is no Oxygen to keep the flame and the candle extinguish.

Answer to Questions: 1) Why did the candle reignite with a match held away from the wick? When the flame was extinguished, it left a trail of smoke which contains bits of wax that have not been fully burned yet. When the flame was then placed on that smoke trail it attracted to the wax in the presence of oxygen and followed that trail until it eventually lit the candle back up. 2. a. Explain how the candle was extinguished with aluminium foil and carbon dioxide. In this experiment, we are observed how the candle flame needs oxygen and wax to burn. Aluminum is a metal and a heat conductor. When the aluminum is place between the wax and flame, oxygen is not able to reach the candle to fuel the flame, then the flame extinguished, while in part E the carbon dioxide is released and with lack of oxygen to fuel the flame, the flame burns out. b) Suggest and explain another method of extinguishing a candle not already used in Part A. by covering the candle with a jar, the flame will extinguish because it will consume all oxygen inside the jar, and since the oxygen is the fuel, once it will runs out, the flame will burn out as well. c) Write out the balanced chemical equation for the reaction that produced the carbon dioxide you used to extinguish the flame. NaHCO3(s) + CH3COOH(aq)  NaC2H3O2 (aq) + CO2(g) +H20 (l) 3) What does the formation of water on the aluminum ice sack suggest about the chemistry of a burning candle? The candle is a hydrocarbon. The combustion of hydrocarbons produce water and carbon dioxide as the products. When candle burns, some water is formed which condenses as a liquid when comes into contact with cold aluminum surface.

4 a) Suggest a reason why the water is sucked up into the glass jar. When the candle burns inside the jar, it uses up the oxygen in the glass jar, reducing the mole of gases inside the jar leading to decrease in the pressure inside, also the produces water vapor from combustion will condense leading to reduction in the gas moles inside the jar. So the water flow to inside the jar to equalize the reduce pressure inside the jar. b) A candle flame will use up oxygen as it burns. However, the consumption of oxygen alone does not explain the observed volume change. What other factor(s) need to be considered? The other factors to take in consideration is : - Candle flames heats up the air inside the jar and when it goes out , the air starts to cool and occupy less space leading to pressure reduction. The higher pressure outside the jar pushes water inside the jar. The water stops rising when the pressure outside equal inside the jar. 6) Explain the difference in the shapes of the two flames (Normal candle and the nearly identical candle in micro gravity flame) shown on page 51 of this manual. The candle flames is yellow flames is primarily due to carbon particles. In addition, the rising hot air is what shapes the flame into a teardrop formation. On Earth, candles can be easily supplied with an abundance of oxygen, fueling the combustion reaction. The heat from the flame causes expanding of products, decreases density and increases buoyancy. At Micro Gravity, the flame is spherical and encircled around the candle wick and oxygen not abundant as on earth. Gravity is necessary for density differences; therefore, buoyancy and convection cannot arise in a zero-gravity environment. With an inability to expand, the spherical nature of the flame is formed. The smaller, circular shape prevents oxygen from reaching the wick. In addition, in Micro-Gravity, the candle has no incandescent soot and the flame temperature is cooler than a flame on Earth. The flame will extinguish and will not continue to combust. Conclusion: Through examination of the various ways and procedurs to manipulate candle flame, In order for a chemical reaction to successfully occur, all reactants much be able to be used to their full potential. In this experiment we learned that a reactant can be disturbed by many factors, eventually preventing the reaction to occur, also there are many factors that can affect the reaction such as oxygen supply, density of the air and pressure....