What will be the minimum pressure required to compress 500 dm3 of air at 1 bar to 200 dm3 at 30°C?
Given that P1 = 1 bar.
V1 = 500 dm3
V2 = 200dm3
As temperature is constant, the final pressure can be calculated by Boyle's law,
P1V1 = P2V2
⇒ 
⇒ P2 = 
⇒ P2 = 2.5 bar
Therefore, minimum pressure required is 2.5 bar.
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