Q3. How will you prove that air supports burning?
By the following steps:
(i) Fix two small candles on a table. Light both the candles. Cover one of the candles with an inverted glass tumbler.
(ii) You must have observed that the candle covered with glass tumbler got extinguished after some time, whereas the other candle continued burning.
(iii) The candle got extinguished because the component inside of the glass tumbler, which supports burning, is limited. Most of the component is used up by the burning candles. However, the other candle is getting a continuous supply of air. This component of air, which supports burning, is known as oxygen.