异极矿的标准生成热力学函数  

Standard thermodynamic functions for formation of hemimorphite

作　　者：尹杏[1] 刘常青[1] 陈启元[1] 张平民[1] 

机构地区：[1]中南大学化学化工学院,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2012年第6期2054-2058,共5页Journal of Central South University:Science and Technology

基　　金：国家重点基础研究发展规划("973"计划)项目(2007CB613601)

摘　　要：采用PE公司的Diamond差式扫描量热仪(DSC)测定异极矿脱去1个水分子所生成的产物Zn4Si2O7(OH)2和异极矿Zn4Si2O7(OH)2·H2O在363～563 K温度范围内的恒压比热容;测定恒压条件下,在573.15～998.15 K温度范围内异极矿加热脱水过程的DSC曲线。将比热容换算成摩尔热容,用最小二乘法分别拟合Zn4Si2O7(OH)2和Zn4Si2O7(OH)2·H2O的摩尔热容与温度的函数关系式;利用相关物质的已知热力学参数,设计热力学循环,计算在标准压强和温度298.15 K时Zn4Si2O7(OH)2和Zn4Si2O7(OH)2·H2O的标准生成热力学函数ΔfHmΘ,ΔfSmΘ和ΔfGmΘ。It temperature of 363-563 K,the isobaric specific heat capacities Cp of dehydrated hemimorphite Zn4Si2O7（OH）2 and hemimorphite Zn4Si2O7（OH）2·H2O were measured with Perkin Elmer Diamond DSC.Under constant pressure,the DSC curves of the heating and dehydrating process in 573.15-998.15 K were obtained.Converting the specific heat capacities Cp to the molar heat capacities Cp,m,the molar heat capacities as a function of temperature were fitted with least square methods.Based on concerned thermodynamic data,a thermodynamic cycle was designed,and the standard molar thermodynamic functions of formation ΔfHmΘ,ΔfSmΘ and Gibbs free energy ΔfGmΘ of Zn4Si2O7（OH）2 and Zn4Si2O7（OH）2·H2O under standard pressure and at temperature of 298.15 K were calculated.

关 键 词：异极矿 标准生成热力学函数 热容 

分 类 号：O642[理学—物理化学]