二溴对甲偶氮羧分光光度法联合测定钡和锶

Successive Determination of Ba and Sr by Spectrophotometrywith Dibromomethyl Carboxyazo

对钡和锶与二溴对甲偶氮羧的显色反应进行了比较研究。在磷酸介质中，Ｂａ２＋反应具有选择性，且允许６倍的Ｓｒ存在。而在硼酸─硼砂缓冲介质中，Ｂａ２＋和Ｓｒ２＋显色配合物的吸光度具有加和性．据此，设计了联合测定钡和锶的新方法，该法用于合成样品中锶和钡的测定，结果满意．

The colour reactions of barium (Ⅱ) and strontium (Ⅱ) with dibromomethyl carboxyazo were studied comparatively. In the medium of H3 PO4, the colour reaction of barium (Ⅱ) is highly selectivity and tolerates the existence of 6 - fold of strontium(Ⅱ). And in the buffer medium of H3BO3 - Na2B4O7,the absorbances of colour coordination compounds for barium(Ⅱ) and strontium(Ⅱ) have an additivity over a certain range of concentrtion.On these grounds, a new method of the successive determination for barium and strontium had been developed.