Fehling's solution

What do you mean by fehling's solution? This is an alkaline solution of a complex copper tartrate & is prepared by adding a solution of CuSO₄ to an alkaline solution of Rochelle salt. Do you know what is rochelle salt? Rochelle salt is sodium potassium tartrate. Remember that this solution is violet in colour . On warming with aldehyde this is reduced to a red precipitate of Cu₂O.