Combustion

1. What are fuels?
2. Paper when burnt produces heat and light.What are these kinds of substances called? Give two other examples of it.
3. What is combustion?
4. What is fuel for our body?
5. Describe an experiment to show that air is necessary for combustion.
6. Why is oxygen called supporter of combustion?
7. A candle flame put in a jar covered with a cardboard is put off after sometime. Why?

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