Consider the reactions:
(a) H3PO2(aq) + 4 AgNO3(aq) + 2 H2O(l) → H3PO4(aq) + 4Ag(s) + 4HNO3(aq)
(b) H3PO2(aq) + 2CuSO4(aq) + 2H2O(l) → H3PO4(aq) + 2Cu(s) + H2SO4(aq)
(c) C6H5CHO(l) + 2[Ag (NH3)2]+(aq) + 3OH–(aq) → C6H5COO–(aq)+ 2Ag(s) +4NH3 (aq) + 2H2O(l)
(d) C6H5CHO(l) + 2Cu2+(aq) + 5OH–(aq) → No change observed.
What inference do you draw about the behaviour of Ag+ and Cu2+ from these reactions ?
(a) Ag ions are reduced to Ag which is precipitated.
(b) Cu2+ (aq) are reduced to Cu which is precipitated.
(c) Ag+ (aq) present in the complex are reduced to Ag which gets precipitated as shining mirror.
(d) Cu2+ (aq) ions are not reduced by C6H5CHO (benzaldehyde) which is a very weak reducing agent.
Therefore from the above reactions, we conclude that Ag+ ion is a stronger oxidising agent than Cu2+ ions.
