Preparation and Analysis of a Silver II Complex

The persulphate oxidation of Ag(I) is indicated by the black colour seen when silver ions catalyse the persulphate oxidation of Cr(III) or Mn(II). The presence of a chelating ligand is expected to stabilise silver(ll). Dipyridyl forms complexes with silver nitrate readily. Persulphate oxidises Ag(I) in the complex to Ag(II) replacing the nitrate as a counter ion. 

The first step in the preparation is to prepare the Ag(I) complex which is then oxidised by persulphate. 

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