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A sample of ammonium phosphate can be prepared by the reaction of aqueous
ammonia and phosphoric acid.
3NH3 (aq) + H₂PO4 (aq)
(NH4),PO4 (aq)
25.0cm³ of 1.25 mol/dm³ phosphoric acid is neutralised by 45.3cm³ of aqueous
ammonia.
(a) Calculate the concentration in mol/dm3 of the ammonia used.
[3]
(b) (i) Show by calculation that 4.66g of ammonium phosphate would be produced.
Assume that the yield is 100%. [Mr: (NH4)3PO4, 149]