亚硝酸根的一个高选择性指示反应的研究——溴酸钾-依来铬青R体系

The Study of A High Selectivity Indicator Reaction of Nitrite——The System of Potassium Bromate-Eriochrome Cyanine R

本文研究了亚硝酸根的一个新指示反应。它基于在稀磷酸溶液中,依来铬青R与溴酸钾的反应受亚硝酸根催化而使吸光度降低。方法sandell灵敏度为1.11×10^(-4)μgN/cm^(2)。有较高选择性。表观活化能为84.52KJ/mol。用于水样中痕量亚硝酸根的测定,对含NO_(2)^(-)3.03μg/L和39.8μg/L的水样变异系数(n=9)分别为2.40%和2.42%。精密度亦佳。

In this paper,a new indicator reaction of nitrite is studied.It is based on the decrease in absorbance of the reaction eriochrome cyanine R with potassium bromate in dilute H3PO4 which is catalyzed by nitrite.The Sandell sensitivity is 1.11×10^(-4)μgN/cm^(2).The method is selective.The apparent activation energy is 84.52KJ/mol.This method has been applied to the determination of trace amounts of nitrite in water samples.The coefficient of variation is 2,40 and 2.42%for water samples of 3.03 and 39.8μg/L of NO_(2)^(-)(n=9),respectively.The precision is also good.