High Frequency Titration of Orthophosphate with Magnesia Mixture

1 High frequency titration of orthophosphate with magnesia mixture 

Prepare a solution which is 0.25 M in magnesium chloride or nitrate and 0.25 M in ammonium chloride or nitrate and 0.75 M in ammonia. Using purest K2HPO4 prepare a 0.3 M solution in deionised water. Deliver from a burette 75-80 cm of this solution in the titration vessel provided with a bar magnet. Add, while stirring well, the magnesia 

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