The effect of fluoride taken directly from fluoride salts and there distilled ions with H2SO4 , Silica gel , and without silica gel on Iron (III) – Sulfosalicylic acid (SSA) complex ,was studied by the photometric method in the visible region at the wave length 495 nm , pH = 2.3 . The absorption decreases linearly with increasing the concentration of fluoride , The best effect was on the non charge complex (FeSSA) which the concentration of SSA not more than twice of the Iron (III) . The calibration curve was studied at various concentrations of the complex , the best one was C(S)=0.0004,C(Fe)=0.0002M , where , the linear range extended to the 25 mg/L for non distilled fluoride and the other which distilled without silica gel , and 50 mg/L for distilled fluorine with silica gel . We applied the results of research to determine fluoride in some fluorine salts and in Syrian phosphate rock , after isolated fluoride by distillation . The amount of fluorine in the studied phosphate rock samples were (2.4 - 2.97)% . The relative standard deviation in the worse case was RSD %= 2.85.
المزيد من المستخلصات حول Indirect Photometric Method to Determine Fluoride using Iron (III) – Sulfosalicylic acid Complex