Answer:

Paper by itself catches fire easily because it has low ignition temperature but when wrapped around an aluminium pipe paper's ignition temperature isn't attained. This is due to aluminium metal absorbing the heat supplied to paper. So it does not catch fire easily.

Answer:

Ignition temperature

1. The lowest temperature at which a substance catches fire is called ignition temperature.
2. A substance cannot catch fire unless it reaches its initial temperature.
3. The Ignition temperature of paper is low, so it catches fire easily.
4. Whereas when a paper is wrapped around aluminum pipe the ignition temperature increases so it does not catch fire easily.
5. This happens because aluminium is a metal, As a result it is a very good conductor of heat and when tries to burn, it absorbs all the heat energy
6. Therefore, due to aluminium being a good conductor of heat, when the paper is wrapped around it does not catch fire.

Explanation:

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