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在盐酸溶液中用亚硫酸钠还原,溴酸钾滴定锑的方法,适合于金属中测定锑;虽然金属中一般含砷量不高,但仍须加热挥发除砷,并通氧气或空气以排除剩余的还原剂。用滤纸还原锑(Ⅴ)至锑(Ⅲ)后,以甲基橙为指示剂硫酸高铈滴定法测定锑,虽然是测定常量锑广泛应用的方法,但存在终点不敏锐还原速度慢的缺点。文献用次甲基蓝-甲基橙为指示剂,硫酸联氨作还原剂,硫酸高铈滴定锑,可获满意结果。本文比较了滤纸、硫化钠等,提出硫脲作还原剂,由于过量试剂在加热时能迅速分解,不致因分解
In hydrochloric acid solution with sodium sulfite reduction, potassium bromate titration antimony method is suitable for the determination of metal antimony; Although the metal generally contains arsenic is not high, but still volatile arsenic, and oxygen or air to exclude the remaining reductant . After the antimony (Ⅴ) to antimony (Ⅲ) is reduced with filter paper, the antimony is determined by titration with methyl orange as the indicator ceric sulfate. Although it is a widely used method for the determination of antimony, it has the disadvantage that the end point is not sharp and the reduction speed is slow. Literature with methyl blue - methyl orange as an indicator, hydrazine sulfate as a reducing agent, titration of cerium sulfate antimony, satisfactory results can be obtained. This paper compares the filter paper, sodium sulfide, etc., proposed thiourea as a reducing agent, due to excessive reagents in the heating can be quickly decomposed, not due to decomposition