Answer to Question #180168 in Organic Chemistry for Ayessa

Question

What is the correct chemical reaction/equation for:

a.) glucose with Fehling's reagent

b.) sucrose with Tollen's reagent

Answer 1

Reaction with Fehling's Solution

A deep blue solution is obtained by mixing Fehling A (aqueous CuSO₄ solution) and Fehling B (aqueous NaOH solution containing a small amount of Roschelle’s salt) in equal volumes. When heated with glucose then Fehling solution gives a red precipitate.

Reaction with Tollen's Reagent

Tollen’s reagent is ammonical silver nitrate solution. When heated with glucose in a clean test tube, a shining mirror gets deposited at the bottom of the tube.

AgNO₃ + NH₄OH → AgOH + NH₄NO₃