Hi
I was wondering if it was possible to disable a pH indicator from working permanently, as in disable it from changing color and reacting to changes in pH by going colorless when mixed with a certain solution.
Yes. Many indicators will irreversibly decolorize when mixed with an oxidizing agent. This is the basis for popular kinetics experiments such as "the decolorization of ..... with bleach". The same with reducing agents (methylene blue will decolorize with borohydride). Finally, good old phenolphthalein decolorizes irreversibly at very, very high hydroxide concentrations.