Schiff's Reagent:
Preparation of Schiff Reagent: 5g of basic fuchsin or rosaniline hydrochloride dissolve in 900ml of hot deionised water. Cool to 50°C and slowly add 100ml of 1N HCl. Cool to 25°C and add 10g of K2S2O5 (potassium metabisulfite or potassium pyrosulfite). Shake for 3 minutes and keep in the dark place at RT(room temperature) for 24 hours. Add 5 grams of fine activated charcoal and shake for 3 minutes and filter. Till Clear solution is obtained. Store at 4°C in a bottle covered with foil. Q) An organic liquid added to Schiff's reagent. The Pink colour is obtained the organic compound is Ans) Schiff's reagent is decolourised by sulphurous acid. The schiff's reagent is then treated with the organic compound to give bright pink colour. Immediate pink/red colour indicates aliphatic aldehyde. This reagent is used to detect aldehyde or ketonic group. aliphatic ketone give reaction very slowly which may be neglected. Explained wit