Скачать или смотреть Oxygen is Necessary for Combustion (Meritnation.com)

Visit http://www.meritnation.com for more videos for your class!

Do you think that oxygen is necessary for combustion to take place? If, so then why? In this video, we will try to get the answers to these questions. In order to prove that oxygen is necessary for combustion, we need to perform a small activity. Fix three burning candles on a table and cover them with glass tumblers whose bases have been removed. The first glass tumbler is placed in such a manner that it rests on two blocks of wood. The second tumbler is placed on the table as such while the third tumbler is placed with its base covered with a glass plate. After sometime, one can observe that the candle in the first setup is burning without any disturbance, while the candle in the second set up flickers for a while producing a lot of smoke and then goes out. In the third set up, the flame goes out as soon as the glass plate is placed on the tumbler. This proves that oxygen is necessary for combustion.