The concentration of iodide (I- ) ions in groundwater isdetermined by first oxidizing I- to I2 andthen converting I2 into an intensely coloredcomplex with the dye brilliant green in the organic solvent toluene. It was observed that a groundwater sample had an absorbance of0.175 while a 3.15μM solution of the colored complex preparedin distilled water exhibited an absorbance of 0.267 at 635 nm in a1 cm cuvet. Measurment also showed that a sample of distilled waterhad an absorbance of 0.019 in the same cuvet and at the same wavelenghth.
Bsaed on this data , determine the absorptivity of the colored complex at 635 nm and the concentration of I- of the groundwater sample. Assume that I- binds to the coloredcomplex in 1:1 ratio.