Photochromic behaviour of potassium hexacyanoferrate(II)-phenolphthalein system

摘要

Potassium hcxacyanoferrate(II)-phenolphthalcin system gives pink colour on exposure to light and it reverts back in dark.The effect of variation of various parameters like pH,light intensity,concentration of phenolphthalcin and concentration of potassium hexacyanoferrate (II),on the rates of forward and backward reactions of this photochromic system has been observed.A tentative mechanism has been proposed.