双波长分光光度法测定水中的钙

DOUBLE WAVE LENGTH SPECTROPHOTOMRTRY FOR DETERMINATION OF CALCIUM IN WATER

本文研究了均三溴偶氮胂（TBA）与钙的显色反应。结果表明,均三溴偶氮胂与钙在PH10.7的NH4OH-NH4Cl缓冲介质中形成1:2络合物,利用双波长分光光度法,以490nm为参比波长, 600nm为测定波长,测得ε490-600=3.1×104,钙量在0-30μg/25ml范围内符合比尔定律。本法用于自来水、河水、井水和锅炉水中钙的直接测定,结果满意。

This article reports color reaction between the homogeneous tribromin azoarsine(TBA) and calcium cation.The result of the reaction indecates that both of them can combine a 1:2 complex compound in buffer solution of NH4OH-NH4CI(pH = 10.7).Otherwise,we use doubl wave length spectrophotometry for determination of the complex compound.Taking 490nm as a reference wave length and 600nm as determina-tion,we have got absorption coefficient ε490-600=3.1 × l04.The linear relationship is subordinated to Bier Law in the concentration scale of 0-30ug / 25ml.This method can be applied to analyse calcium in tap water;river;water well.