With the help of an experiment, show that oxygen (air) is necessary for the burning of a candle.

To show the experiment we have to fix three lighted candle on a table, and put a glass chimney over it.

fig a	fig b	fig c

The chimney (fig a) rested on a wooden block in such a way that air can enter the chimney – the candle will continue burning, because it is getting air from the wooden blockThe chimney (fig b) rested on the table with no way for air- the candle flickers and gives smokeThe chimney (fig c) rested on table and covered from top with glass plate – the candles goes off as the air is not available.