几种二元弱酸的电离常数及其与Cu^(2+)形成配合物的稳定常数的测定  

Determination of Ionization Constants of Binary Acid and Stability Constants of Its Complexes with Cu^(2+)

作　　者：王英[1,2] 付虹[2] 王露[2] 高恩军[2] 

机构地区：[1]岫岩满族自治县岫岩高级中学,辽宁鞍山114300 [2]沈阳化工大学应用化学学院,辽宁沈阳110142

出　　处：《沈阳化工大学学报》2013年第4期289-291,326,共4页Journal of Shenyang University of Chemical Technology

基　　金：国家自然科学基金资助项目(21171118)

摘　　要：用电位滴定法测定几种二元弱酸在离子强度μ=0.1(KNO3),V(乙醇)/V(水)=10%混合溶剂中的电离常数及其与Cu2+形成的MAB(M=Cu2+;A=水杨酸、5-硝基水杨酸、5-甲氧基水杨酸;B=丙二酸、苯丁基丙二酸)型配合物的稳定常数.讨论弱酸中取代基官能团对电离常数及配位稳定性的影响.结果表明:在含有芳环的配体水杨酸中引入吸电子基团时电离常数降低,引入推电子基团时电离常数升高.对于丙二酸配体,增长碳链电离常数增加,配体芳环之间的堆砌作用可以增强配合物的稳定性.Ionization constants of the mixed solvent of several binary weak acid in ionic strength/z = 0. 1 （ KNO3 ）, 10% ethanol/water （V/V） were determined by potentiometric titration. The stability constants of MAB （M = Cu2＋ , A = salicylic acid,5-nitro salicylic acid ,5-methoxy salicylic acid;B = malonic acid, benzene Ding Jibing diacid） type coordination compounds formed by these several binary weak acid with Cu2 ＋ were measured by the same method. The effects of substituent functional groups in the weak acid on the ionization constants and coordination stability were discussed. The results showed that the dissociation constant of salicylic acid ligand containing aromatic ring declined when introducing electron-withdrawing groups. The ionization constants rose when introducing push electronic groups. For malonic acid ligand, i- onization constant increased when carbon chain length increased, and ligand stack effect between the aro- matic rings could strengthen the stability of the coordination compounds.

关 键 词：二元弱酸 电离常数 电子效应 稳定常数 

分 类 号：O611.3[理学—无机化学]