What is meant by compressibility factor of gases? How does its value deviate from that of an ideal gas in case of real gases and what does it indicate?

What is meant by compressibility factor of gases? How does its value deviate from that of an ideal gas in case of real gases and what does it indicate?
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Answer :

Ans. It is the ratio of the product PV to nRT. Z = PV/nRT. For ideal gas its value is unity. Z < 1 indicates negative deviation i.e. gas is more compressible due predominance of attractive forces. Z > 1 indicates positive deviation i.e. gas is less compressible due predominance of repulsive forces.
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Related questions

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