摘要
金属离子酸的离解常数可推导为Ka=Kw·K_(MOH)及Ka_n=Kw·K_(M(OH)n)。在金属离子存在下滴定游离酸,可以作为混合酸进行理论处理,使用相同的滴定条件与等当点pH计算公式。在加入掩蔽剂滴定时,可以使用金属离子酸的条件稳定常数作出相似的理论处理。
The dissociation constant of metallic ion acids can be derived as K_(ai)=K_w·K_(M(OH)i)·Then the titration of a free acid in the presence of metallic ion can be theoretically treated as a mixed acid, using the same titration conditions (e.g.△lgK_aC≥6) and the some pH calculation formulae. As the ΔlgK_aC is too small to satisfy the titration condition and the masking agent is added, we can calculate the conditional dissociation constant of metallic ion acid by aM(L) and lgK_a'=lgK_a-lgαM(L), and then estimate the AlgK_aC and calculate the pH.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
1992年第1期54-57,共4页
Chinese Journal of Analytical Chemistry
关键词
金属离子酸
离解常数
游离酸
滴定
Metallic ion acid, Dissociation constant, Free acid titration.
