Combustion

1. What is ignition temperature?
2. A piece of paper is burnt with the help of a matchstick but wood is not. Why?
3. Explain how is it possible to boil water in a paper cup on a spirit lamp?
4. White phosphorus catches fire spontaneously during summer. Why?
5. Tip of a matchstick contains chemical that helps in catching fire but how does wood catch fire?
6. The flame of a burning candle goes off when we blow over it strongly.Give two reasons for it.
7. List three reasons necessary for sustaining combustion.

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