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Explain combustion and combustible along with examples.
Why isn't hydrogen gas used as a domestic or industrial fuel, although it has a very high calorific value? State three reasons for the answer.
Why does the matchstick start burning on rubbing it on the side of matchbox?
State the difference between burning of a candle and burning of a fuel like coal
What is acid rain? Write its effects.
On putting glass over a lighted candle, the candle flame flickers and produce smoke, why so?
What is forest fire?
When the clothes of a person catch fire, the person is covered with a blanket to extinguish fire, explain why?
Explain complete combustion.
It is observed at petrol pumps and airports, that hydrocarbon fire extinguishers are used, instead of soda-acid fire extinguisher. Give reasons why.
What do you mean by ignition temperature? Why a matchstick dose not catch fire on its own at room temperature?
Explain how water gets boiled in paper cup without burning it.
Food is a fuel for the body. Justify this statement.
Why does a piece of paper burn with yellow flame? Give a reason.