摘要
本文报道了Cr(Ⅵ)-C_(12)H_8N_2-NaNO_2-NH_3-NH_4Cl(pH9.4)体系极谱催化波机制的研究.阐明它不是氢催化波.而是Cr(Ⅲ)的多元配合物中NO_2^-被催化还原,同时溶液中的NO_2^-又参与了平行电极反应的催化反应.活性多元配合物的组成为:Cr(Ⅲ)·(C_(12)H_8N_2)·(NO_2^-)_2·(NH_3).
A new viewpoint elucidating the mechanism of a highly sensitive polarographic catalytic wave of Cr(Ⅵ) in the medium of 1,10-phenanthroline-nitrite-NH3-NH4Cl (pH9. 4) is presented. This wave is not a catalytic hydrogen wave, but a catalytic (EC-EC') reaction in which Cr(Ⅵ ) is firstly reduced to Cr( Ⅲ ) , then it forms a multi-coordination compound A (as electroactive species) in the following chemical reaction. In the second step of the electrode reaction, the ligand NO2- in the compound A is reduced, then the product of A is oxidized by NO2- in solution to regenerate the starting material A again. The composition of the multi-coordination compound and the conditional formation constant for various ligands are determined.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
1989年第12期1189-1193,共5页
Chemical Journal of Chinese Universities
基金
国家自然科学基金
关键词
铬
催化波
条件形成常数
混配化合物
Chromium, Catalytic wave, Conditional formation constant, Multi-complex
