a solution of fuchsine decolorized by treatment with sulfur dioxide that gives a useful test for aldehydes because they restore the dye's color — compare feulgen reaction.

Application

Schiff's reagent is used to distinguish between aldehydes and ketones. Ketones do not react with Schiff's reagent; however, aldehydes react with Schiff's reagent. Complete answer: The Schiff test is a chemical test used to check the presence of aldehydes in a solution.