Pharmacy Study Material

Free pharmacy material Precipitation Titrations INTRODUCTION Precipitation titrations are mainly based on the formation of the precipitate by the reaction of the sample with precipitating agents. The precipitate formed is the less soluble compound. Ag + + Cl − AgCl (ppt.) The number of precipitating agents that can be used is limited because of the slow action to form the precipitate. This method is mainly used in the determination of the halides. THEORY The theory involved in the precipitation titration is the addition of the sample solution to the titrant in which the precipitating agent forms the precipitate and the end point is detected by the indicators. Ag + + I − AgI (precipitate) KI + AgNO 3 AgI + KNO 3 ↓ The precipitating reagents are limited because of their less precipitate formation. M + D ↔ MD The precipitate formation constant is given by the following equation: where {M} is the concentration of the sample io...