黄铜中铅的测定,过去我室采用硫酸铅重量法,铬酸铅容量法和络合滴定法。重量法和容量法手续麻烦、费时,不能满足生产要求;络合滴定法虽然克服了以上两种方法的缺点,但测定较低含量的铅时,需要加入大量的氰化钾,易造成终点不明显。根据以上情况,我们拟定了黄铜中铅的光度法,系在pH=10的氨-氯化铵缓冲溶液中,铅与吡啶-(2-偶 Determination of lead in brass, in the past I used lead sulfate weight method, lead chromate volumetric method and complexometric titration. Gravimetric and volumetric procedures inconvenient and time-consuming, can not meet the production requirements; Although the complexation titration overcome the shortcomings of the above two methods, but the determination of low levels of lead, you need to add a lot of potassium cyanide, can easily lead to the end obvious. Based on the above, we developed a spectrophotometric method for the determination of lead in brass. In the ammonia-ammonium chloride buffer solution at pH = 10, lead and pyridine-