COLORIMETRIC DETERMINATION OF ETHANOL IN THE PRESENCE OF METHANOL AND OTHER SPECIES IN AQUEOUS-SOLUTION

Ethanol is coupled with diazotized p-aminobenzoic acid, to give a coloured product with maximum absorption at 436 nm. The coloured product has a molar absorptivity of 1.02 x 10(4)l.mole-1.cm-1 and Beer's law is obeyed over the range 0.5-4.0 mug/ml. The relative standard deviation is less than 4.76% and the relative errors are within -2.89-3.9%. The suggested method is rapid, simple, selective and sensitive.