摘要
本文用光度法研究了4-(2-噻唑偶氮)-间苯二酚(TAR)的酸碱平衡及TAR与Cd(Ⅱ)的配合反应。用图解法和MINISPEF程序计算得到TAR的逐级离解常数(pKa_1=0.099,pKa_2=6.24,pKa_3=9.64),确定TAR与Cd(Ⅱ)的体系中,存在MHR、MR、MR_2三种配合物。MHR、MR、MR_2的最大吸收波长分别在510nm、505nm、530nm,稳定常数分别是,1gβMHR=13.40,1gβMR=7.19,1gβMR_2=11.39。本文还给出了测定微量Cd(Ⅱ)的分光光度方法。
Acid-basic equilibrium of 4-(2-thiazolylazo)-resorcinol(TAR) and its complex reaction with Cd(Ⅱ) were studied spectrophotometrically. Consecutive dissociation constants of TAR were obtained by graphical method and MINISPEF program, which are 0.99, 6.24 and 9.64 for pKa_1, pKa_2 and pKa_3 respectively. It was demonstrated that there are MHR, MR and MR_2 of complexes of TAR with Cd(Ⅱ) in aqueous-ethanol solutions. Absorption maxima of MHR,MR and MR_2 are at 510nm. 505nm and 530nm, and their stability constants are 13.40, 7.19,and 11.39 respectively. Spectrophotometry of micro amounts of Cd(Ⅱ) was given.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
1989年第11期984-989,共6页
Chinese Journal of Analytical Chemistry
关键词
镉
噻唑偶氮
苯二酚
分光光度法
Spectrophotemetry
4-(2-Thiazolylazo)-resercipol(TAR)
Graphical method
MINISPEF progtam
Dissociation constant
Stability constant
