【摘要】 本文研究了LaNi₄Cu在同样二份合金试液中测定分量的快速分析方法,终点锐敏,方法快速、简便,结果可靠。更多还原

【Abstract】 La, Ni and Cu in LaNi4Cu alloy sample were determined by a rapid chelatometric titration. EDTA forms highly stable complexes with La, Ni and Cu, and La .forms insoluble LaF8 with F-, and Cu forms a stable complex with S2O32-. In a weakly acidic medium ( pH5-6 ) , excess EDTA was added to the sample solution, and the free EDTA was titrated with PbAca standard solution to give total ( La+Ni+Cu ) content. On the addition of excess NaF, the EDTA released from La complex was titrated with PbAc2 to determine La content. On the addition of excess Na2S2O3, the EDTA released from Cu complex was titrate’d with PbAca to determine Cu content. Then Ni content was determined by differential analysis. The results obtained by this method were in agreement with those obtained by X-ray fluorescence analysis.更多还原