Enthalpy-Concentration Diagram for Aqueous Ethyl Alcohol Fig

2-10 Enthalpy -concentration diagram for aqueous ethyl alcohol. Reference states Enthalpies of liquid water and ethyl alcohol at 0 °C are zero. NOTE In order to interpolate equilibrium compositions, a vertical may be erected from any liquid composition on the boiling line and its intersection with the auxiliary line determined. A horizontal from this intersection will establish the equilibrium vapor composition on the dew line. Bosnjakovic, Technische Thermodynamik, T. Steinkopjf, Leipzig, 1935.) 

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