分光光度法测定锡钴合金镀液中的钴

Spectrophotometric determination of cobalt in tin–cobalt alloy plating solution with picramazochrom

pH=10的柠檬酸铵-氨水溶液中，钴与苦氨酸偶氮变色酸反应形成绿色配合物，其最大吸收波长为650nm，表观摩尔吸光系数为2．62×10^4L／（mol·cm）。在25mL溶液中，钴含量在0～50μg范围内遵循比尔定律。样品分析表明，该法的相对标准偏差小于2％。

Cobalt reacts with picramazochrom to form a green complex with a apparent molar absorption coefficient of 2.62 x 10AA^4L/（mol·cm） at the wavelength of 650 nm in a solution consisting of ammonium citrate and ammonia at pH 10. Beer＇s law is obeyed in the range of 0-50 μg cobalt in a 25 mL bath. Sample analysis showed that the relative standard deviation was less than 2%.