Abstract
Square-wave polarographic determination of trace amounts of bismuth by separating coprecipitation with zirconium hydroxide was investigated. Thirty-two mg of zirconium oxychloride was added to a (501000) ml solution containing (0.633.15) μg of bismuth, and pH of the solution was adjusted to 9.7 with ammonia-water (1 : 1). The precipitate was separated by filtration and then dissolved in 25 ml of 4 M hydrochloric acid. The solution was diluted to 50 ml with distilled water, and a portion of this solution was subjected to the square-wave polarographic determination. Bismuth was collected most effectively with zirconium hydroxide from the solution adjusted to pH 9.7 with ammonia-water (1:1). The polarographic peak height was in linear relation with the concentration of bismuth in the range of (0.633.15) μg. The coefficient of variation was 1.0%. Among the various foreign ions examined, copper, antimony, zinc and nickel interfered with the polarographic determination remarkably.
