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Lets do a quick recap. Make notes if you need to.

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1)What happens to the molecules of a gas when the gas is heated?

2) How does the particle model explain temperature?

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a)  Describe, in terms of particles, how a gas exerts a pressure.

b)  Suggest why the pressure inside a bicycle tyre increases when you pump more air into it.

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a)  How do we know that the mass of gas is constant?

b) Explain, using ideas about energy, why the pressure of gas increases if it gets hotter.