Question #883ac

1 Answer
Apr 1, 2017

#12(NH_4)_2MoO_4 + H_3PO_4##(NH_4)_3PMo_12O_(40)#

(not balanced)


The diagram may be best:
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Graphic from

Phosphate can form complexes with many di and tri-valent metals. Note that other acids may be used for pH control other than the #HNO_3# shown in the equation.

This is a common colorimetric test for phosphate ions in solution, important for environmental analyses.

Phosphate + ammonium molybdate + ammonium metavanadate ----> colored complex.
Phosphate(V) ions react with ammonium molybdate to produce a coloured complex. RSC Phosphate by molybdate assay student.pdf