14 Questions Available
Showing 14 questions on this page
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?
Explain complete combustion.
What is acid rain? Write its effects.
What is forest fire?
State the difference between burning of a candle and burning of a fuel like coal
On putting glass over a lighted candle, the candle flame flickers and produce smoke, why so?
When the clothes of a person catch fire, the person is covered with a blanket to extinguish fire, explain why?
Explain combustion and combustible along with examples.
Food is a fuel for the body. Justify this statement.
It is observed at petrol pumps and airports, that hydrocarbon fire extinguishers are used, instead of soda-acid fire extinguisher. Give reasons why.
Explain how water gets boiled in paper cup without burning it.
Why does a piece of paper burn with yellow flame? Give a reason.
What do you mean by ignition temperature? Why a matchstick dose not catch fire on its own at room temperature?