1,2-dichloroethane-n-heptane, 1,2,-dichloroethane-n-butanol계와, n-heptane-n-butanol계의 혼합열을 15 ℃, 25 ℃, 35 ℃와 45 ℃에서 측정하였으며 이로부터 partial heats of mixing값들을 구한후 같은 온도에서 과잉 열역학적 성질을 계산하였고, partial excess Gibbs free energy를 이용하여 등온기액평형치를 추산하였으며, 이 값을 혼합열로부터 계산된 과잉 Gibbs free energy와 함께 total pressure법으로 계산된 35 ℃와 45 ℃에서의 값들과 비교하여 보았고 더욱 150 ㎜Hg와 300 ㎜Hg에서 등압기액평형치를 추산하였다.

Heats of mixing for the 1,2-dichloroethane-n-heptane, 1,2-dichloroethane-n-butanol and n-heptane-n-butanol systems were measured at 15 ℃, 25 ℃, 35 ℃ and 45 ℃. From the heats of mixing, partial heats of mixing were calculated, and then excess thermodynamic properties for each binary solutions were calculated. Using the partial excess Gibbs free energy, the values of isothermal vapor-liquid equilibrium were estimated. The calculated excess Gibbs free energy and isothermal vapor-liquid equilibrium data from heats of mixing were compared with those by total pressure method at 35 ℃ and 45 ℃. Furthermore, the isobaric vapor-liquid equilibrium data were estimated at 150 ㎜Hg and 300 ㎜Hg.