偶氮胂(Ⅲ)高灵敏度法测定痕量铬的研究

Studied on Highly Sensivive Spectrophotometric Determination of Trace Chromium(VI) with Arsenazo Ⅲ

研究了偶氮胂(Ⅲ)与CrO7 2 -的褪色反应 ,建立了一种新的光度法测定痕量Cr(Ⅵ)方法 ,发现其在硝酸介质中具有高灵敏的褪色反应,摩尔吸光系数达4 .8×106,Cr(Ⅵ)量在0 -0 .8Mg/25ml范围内符合比耳定律 .

The fading reaction of arsenazo Ⅲwith Cr2O7 2-was studied, and a new spextrophtometric method for determining trace Cr(VI) was developed .In the medium of nitric acid ,the reaction has high sensitivity.The molar absorptivity is 4.8×106 L.mol-1 cm-1,and Beer's law is obeyed for Cr(VI) in the range of 0-0.8mg/25ml.