可逆反应的热力学判据及可逆电池反应熵变的推演  

Thermodynamic Criteria of Reversible Reaction and Deduction of Entropy Change of Reversible Battery Reaction

作　　者：孟超 李昕[1] 李春龙 MENG Chao;LI Xin;LI Chun-long(School of Materials Science&Engineering,Beijing Institute of Fashion Technology,Beijing 100029;Panjin North Asphalt Company Limited,Liaoning Panjin 124000,China)

机构地区：[1]北京服装学院,北京100029 [2]盘锦北方沥青股份有限公司,辽宁盘锦124000

出　　处：《广州化工》2023年第23期116-118,共3页GuangZhou Chemical Industry

基　　金：北京服装学院高水平教师队伍建设专项资金资助项目(BIFTXJ202221);北京服装学院教育教学改革项目(KCSZZT-2216)。

摘　　要：针对教材中可逆反应热力学适用条件模糊及可逆电池反应熵变的推演过程缺乏,探讨可逆电池反应和可逆化学反应的共性及差异,推导出二者的热力学判据,并区分了广义吉布斯自由能和狭义吉布斯自由能。对于可逆电池反应,探讨直接使用dG=-SdT+Vdp在纯物质模型下求解反应熵变的物理意义及有限条件,从化学反应角度解析热力学基本方程的适用性并推导出可逆电池反应吉布斯自由能变化随温度的变化率。结果表明,引入化学势权重项求解出的偏微分方程与纯物质反应熵变的差值为混合熵变的负值。论述和结果可为可逆反应及反应熵变的推演提供重要补充,为理解热力学在化学反应中的演绎和应用提供重要思路和理论解析。In view of the fuzzy thermodynamics applicable conditions of reversible reaction and the simple deduction process of entropy change of reversible battery reaction in the textbook,the similarities and differences between reversible battery reaction and reversible chemical reaction were discussed,and the thermodynamic criteria under reversible conditions was deduces,then generalized Gibbs energy and the narrow Gibbs energy were defined.For reversible battery reaction,the physical significance and applicability about directly using dG=-SdT+Vdp were discussed and analyzed to obtain the reaction entropy change,then the entropy change was deduced in reversible battery reaction.The result showed that by introducing the chemical potential summation term would create the different value of entropy from using dG=-SdT+Vdp,which was the negative value of the mixing entropy.An important supplement was provided to the corresponding contents of textbooks,which could promote better understanding the thermodynamics in chemical reactions.

关 键 词：可逆反应 吉布斯自由能 化学平衡 物理化学 

分 类 号：O642[理学—物理化学]