Study on the Ternary Heteropolyacids in the Systems of P-Mo-W and As-Mo-W as well as their Application in the Spectrophotometric Determination of Low Tungsten

摘要

The colored associated compounds of phosphomolybdotungstate and arsenomolybdotungstate with crystal violet are intro-duced.Their main characters have been studied.These two associated compounds may be used to determine low tungsten withfairly high sensitivity and selectivity.Their strong point is that the interference of molybdenum can be overcome.In the presenceof polyvinyl alcohol.tungsten can be determined directly in the aqueous solution.