how will you show that air supports burning
Answers
Answer:
To prove that air supports burning, let's take two lighted candles.
1) Put one candle in a tumbler containing water and cover it with an inverted glass.
2) Put the second candle in open air. After some time, this covered candle gets extinguished and the water level rises up in the glass.
3) This happens because oxygen present inside the air in the glass was used up completely.
This experiment shows that air is necessary for burning.
Explanation:
HÔPË ÏTẞ HÉLPFŪLL
PLS MARK AS BRAINLIEST
Answer:
Experiment: Cover a burning candle with a pitcher so that the candle is in an air-tight room sealed by the water at the ground. Observations: After some time, the candle dims and goes out. Just before the candle dies, the water level rises to almost 1/10 th of pitcher height. No air bubbles are seen. The water level stays up for many few minutes more.
The chemical aspect: oxygen O2 and paraffin Cn H2n+2 react. The burning produces water H 2O and carbon dioxide C O 2. For n=1 we balance the equation as follows:
2 O2 + C H 4 = C O 2 + 2 H 2 O
Because twice as much oxygen is burned than carbon dioxide released, the air volume decreases. The physical aspect: the candle heats the air and expands it. 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. The temporary temperature change delays the rise of the water. As several readers have pointed out, also the water condensation should be mentioned. While water is initially gas, it condenses and helps to delay the effect.
Summary: There are two different effects. Both a chemical and a physical reasoning are needed to explain what we can see. Both physics and chemistry matter. The initial cancellation effect can confuse the observer. Mathematics plays a role when the chemical equations are balanced.