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Q5: 1kg water at 333.15 K is compressed isothermally from 1 bar to 500 bar. Knowing that the pressure and volume are related to each other through the following relationship: a av . T = (P + b) Where a = 0.125 L/kg and b = 2.7x103 bar, a) how much is the work done? b) Comment of the sign of the work