【摘要】 用全自动低温绝热量热计测定了水和正丁醇二元体系(0.716H2O+0.284n-C4H9OH)在78~320K温区的摩尔热容Cp,m.建立了Cp,m与温度T的函数关系.结果表明,该水和正丁醇二元混合体系在(111.9±1.2)K发生玻璃化转变,在(179.26±0.77)K和(269.69±0.14)K发生分别对应正丁醇和水的固-液相变.获得了水的相变焓和相变熵.计算了以298.15K为基准的混合物的热力学函数.更多还原

【Abstract】 The molar heat capacity values of the binary system composed of 0.716 molar fraction H₂O+0.284 molar fraction n-C₄H₉OH were measured by an adiabatic calorimeter in the temperature range from 78 K to 320 K.The functional relationships of heat capacity with respect to thermodynamic temperature were established.Glass-transition occurred at（111.9±1.2）K.The phase transitions took place at （179.26±0.77）K and （269.69±0.14）K corresponding to the solid-liquid phase transitions of n-butanol and water, respectively. The phase-transition enthalpy and entropy of water were calculated. The thermodynamic functions of the binary systems relative to 298.15 K were derived based on the relationships of the thermodynamic functions and the function of the measured heat capacity with respect to temperature.更多还原