【摘要】 硫酸介质中和有KBr存在下 ,碘酸根对罗丹明B有褪色作用 ,且褪色的程度与碘酸根存在量有关 ,从而建立了光度法测定碘的新方法。在 0 0 6mol/LH2 SO4 中 ,吸光度至少能稳定 2 4h。方法的最大吸收波长 5 42nm ,表观摩尔吸光系数为2 2 7× 10 4 ,在 2 5mL溶液中碘质量在 0～ 60 μg范围与罗丹明B褪色的程度呈线性关系。方法简单、快速、准确、选择性好 ,应用于测定加碘盐中碘 ,结果满意。更多还原

【Abstract】 In the medium of H₂SO₄ and in the presence of KBr,the color of rhodamine B oxidized by iodate can be faded,and the degree of color fading is proportional to the concentration of iodine,and a new spectrophotometric method for determination of iodine is reported.In the 0.06mol/L H₂SO₄ medium,the color solution is stable at least for 24h.The maximum absorption of color solution is at 542nm,with a molar absorptivity of 2.27×10⁴.Beer’s law is obeyed from 0, to 60μg/25mL of iodine.The method is simple,rapid,accurate,selective and has been used for the determination of iodine in salt adding iodine with satisfactory results.更多还原