【摘要】 对2-(5-氯-2-吡啶偶氮)-5-二乙基氨基酚(5-C l-DEPAP)作锌的络合滴定指示剂进行了实验。在pH 5.5的HAc-NaAc介质中,以5-C l-DEPAP作指示剂,EDTA标准溶液滴定锌,溶液颜色由紫红色变为亮黄色,终点变化敏锐,易于观察,锌量在0~25 mg与EDTA消耗量成正比。方法用于化学试剂和铝合金中锌的测定,5次测定的RSD小于0.1%。结果表明,5-C l-DEPAP符合络合滴定对指示剂的基本要求,扩大了该试剂的应用范围。更多还原

【Abstract】 An accurate and selective method for the determination of zinc by complexometric titration was developed.In the medium of acetic acid-sodium acetate(pH=5.5) and with 2-(5-chloro-2-pyridylazo)-5-diethylaminophenol(5-Cl-DEPAP) as indicator,the amount of zinc is directly in proportion to EDTA solution consumed in a range of 0~25 mg of zinc with a sharp end point.The method has been applied to the determination of zinc in chemical reagents and aluminum alloy with precision of less than 0.1% RSD(n=5).更多还原