4. Take a beaker with some water and place a lighted candle in standing
position in it. Now cover the candle with a test tube to cut off it air supply. For how
long does the candle keep on burning? How much water rises up in the test tube?
Why did it happen so? Explain with diagram. You can perform this experiment with
utensils available at your home in case of non availability of the beaker and test tube.
Answers
Answer:
1.The candle will stop burning as the oxygen supply is cut and the water will rise a little in test tube. Explanation: Because twice as much oxygen is burned than carbon dioxide released, the air volume decreases.
2. Explanation:Because twice as much oxygen is burned than carbon dioxide released, the air volume decreases. ... This cancels the depletion of the oxygen temporarily and the water level stays down. When the oxygen is depleted, the candle goes out and the air cools. The volume of the air decreases and the water rises.
3. Candle wax is a form of hydrocarbon. When it burns, oxygen (from air) reacts with the wax to form two new gases; carbon dioxide and water vapour. Some of the carbon dioxide would dissolve into the water and most of the water vapour would condense back into liquid water.
4. The evaporation of the water to water vapor as the candle burns, and the cooling that occurs when the candle goes out, cause lower air pressure inside the glass than outside. The water is pushed into the glass until equilibrium is reached.) Air cools when the flame goes out.
5. Most candles are made of paraffin, a heavy hydrocarbon derived from crude oil. Burning a paraffin candle for one hour will release about 10 grams of carbon dioxide.
6. A lit candle needs to draw oxygen from the air in order to continue burning. ... Thus, oxygen inside the glass jar will decrease and it gets filled with carbon dioxide, and eventually the candle's flame will Extinguish.
7. With just the open flame above the water's surface, this process will transform the candle into a hollow tube of wax. ... The water surrounding the candle is the secret to this "trick." It keeps the exterior of the candle at a cool temperature, so the area touching the water never melts.
8. The shortest candle will go out first because carbon dioxide is more dense than air and will settle at the bottom and put out the flame.
9. This happens because oxygen in the air inside the glass tumbler is utilized in burning the candle. All the oxygen gets converted into carbon dioxide. Carbon dioxide does not support burning and hence candle stops burning.
10. Steam is the wet mist that forms above boiling water as the hot, invisible water vapor mixes with cooler surrounding air. Evaporation happens when a liquid substance becomes a gas. ... The molecules move and vibrate so quickly that they escape into the atmosphere as molecules of water vapor.
11. Now a burning candle produce carbon dioxide and carbon monoxide. In between this carbon monoxide is toxic and poisonous for human health , by creating carboxi haemoglobin in RBC which reduce the oxygen level in blood. ... Decreased in oxygen level is also a point for this issue. It will cause asphyxiation hazard.
12.Candle jars usually come with a lid, which can be used when it's time to extinguish the flame. Simply blow out the candle gently and then cover immediately with the lid to prevent dust and dirt from getting on the wax and wick.