How will you show that air is necessary for combustion? - Burn a candle . now invert a glass jar over it. You will see the candle gets extinguished on its own after sometime. This shows that oxygen which is found in air is need for combustion., What is atmosphere? - Our earth is surrounded by a blanket of air. We cannot see it but it is present all around us. This blanket is air around the earth is called atmosphere., Traffic police officers should cover their nose and mouth with cloth. Give reason. - It is because vehicles release more smoke and dust in to air, thus traffic police officer covers his nose and,

AIR AROUND US 6

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