摘要
采用pH电位滴定法,于温度25℃条件下,获取半胱胺盐酸盐的各级加质子常数（lgK1H=10.92,lgK2H=8.25）、离解常数（Ka1=5.62E-09,Ka2=1.20E-11）及其与Zn（Ⅱ）形成配合物的稳定常数（lgk5=36.74）、热力学函数（△rHm=-157.14kJ/mol,△rSm=176.74J/（mol·K）,△rGm=-209.60kJ/mol）,并计算各pH条件下半胱胺盐酸盐与Zn（Ⅱ）配合的条件稳定常数。计算得Zn（Ⅱ）与半胱胺盐酸盐配位反应的热力学函数△rGm〈0、△rHm〈0、△rSm〉0,证明反应过程为自发放热。半胱胺盐酸盐与Zn（Ⅱ）形成配合物的稳定常数和条件稳定常数均很大,表明形成的半胱胺锌很稳定。
Under the temperature of 25℃, pH potentiometric method was used to obtain protonation constant （lgK1H=10.92,lgK2H=8.25） and the dissociation constant （Ka1=5.62E-09,Ka2=1.20E-11） of cysteamine hydrochloriden,and the stability constants（lgk5 =36.74） and thermodynamic functions（△rHm=-157.14kJ/mol,△rSm=176.74J/（mol·K）,△rGm=-209.60kJ/mol） of the complex of cysteamine hydrochloride with Zn（Ⅱ） ions. The conditional stability constants at different pH were also calculated. Zn（Ⅱ） ions and cysteamine hydrochloride is revealed as a spontaneous exothermic reaction process,according to the result of △rGm〈0、△rHm〈0、△rSm〉0. The stability constants and conditional stability constants of complex were large, showing that the complex of cysteamine hydrochloride with Zn（Ⅱ） ions was very stable.
出处
《分析科学学报》
CAS
CSCD
北大核心
2016年第6期857-860,共4页
Journal of Analytical Science
基金
广东省工程技术研究中心认定专项(No.2013B070704081)
广东省科技计划(No.2014A020208131
2013B091500095)
广州市科技计划(No.HD14CXY008
201508020048)
关键词
稳定常数
热力学函数
条件稳定常数
Stability constants
Thermodynamic functions
Conditional stability constants
