稀土硫酸盐热容计算方法研究

A STUDY OF THE METHOD FOR ESTIMATING THE HEAT CAMCITY OF RARE EARTH'S SULPHATES

本文研究了固体硫酸盐摩尔热容Cp（T）的计算方法，提出物质热容可以由组成该物质的原子集团的热容贡献值求得，并根据实验数据计算得到了SO3原子集团对硫酸盐的热容贡献值Cp；SO3（T）；根据稀土氧化物摩尔热容Cp，MnOm（T）和SO3的的热容贡献值Cp；SO3（T），本文计算得到了稀土硫酸盐的摩尔热容Cp（T）。

Thermochemical calculations are necessary in the predictions of chemical equilibria. Unfortunately there are no experimental thermochemical data in the literature for a number of substances, so it is important to study the method for estimating the missing . data. Of the methods now available for estimating the heat capacity, none is sufficiefitly general to permit accurate estimation of the constants in the heat capacity equations of sulphates. The present work was directed toward the development of an accurate and simple method for estimating the heat capacity equatiolls of sulphates. The Neumann-kopp rule has been modified. It is suggested that the heat capacities of sulphates equal to the sum of the heat capacity contributions of metal oxides and SO3, which they are composed of The heat capacity equations of metal oxides have been used as the heat capacity contributions to sulphates. The SO'3s heat capacity contribution has been calculated from the experimental data of a number of sulphates. The heat capacity equations of rare earth's sulpliates havebeen derived as follows:where M represents the metal atom, n and m are the numbers of metal atoms and SO_4~2respectively.