For water at 25 C, dps /dTs = 0.189 kPa/K (ps is the saturation pressure in kPa and Ts is the saturation temperature in K) and the specific volume of dry saturated vapour is 43.38 m3/ kg. Assume that the specific volume of liquid is negligible in comparison with that of vapour. Using the Clausius-Clapeyron equation, an estimate of the enthalpy of evaporation of water at 25 C (in kJ/kg) is

For water at 25 C, dps /dTs = 0.189 kPa/K (ps is the saturation pressu

1.	For water at 25 C, dp_s /dT_s = 0.189 kPa/K (p_s is the saturation pressure in kPa and T_s is the saturation temperature in K) and the specific volume of dry saturated vapour is 43.38 m³/ kg. Assume that the specific volume of liquid is negligible in comparison with that of vapour. Using the Clausius-Clapeyron equation, an estimate of the enthalpy of evaporation of water at 25 C (in kJ/kg) is
A.	2445.25
B.	2553.25
C.	2543.25
D.	2443.25
Answer» E.

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