Some Properties of Cerous and Ceric Salts

In acid solutions, ceric salts are powerful oxidizing agents. Simultaneous to the oxidization, they are reduced into cerous salts according to the half-redox equilibrium 

The redox potential of the couple Ce /Ce strongly depends on the nature and concentration of the present acid, as the different values of formal potentials indicate (see Table 20.2). 

We notice that changes are important. We notice also, and overall, that Ce is a very strong oxidizing agent. 

One of the characteristics of the chemistry of ceric salts is the formation of complexes by ceric ions Ce +. For example, the complexes [Ce(S04)4 ], [Ce(S04)3 ], etc., and [Ce(N03)6 ], [Ce(N03)s ] are formed in sulfuric and nitric acid, respectively. Even with perchlorate ions, which are not known to give complexes easily, Ce gives the complex [Ce(C104)6 ] in perchloric acid medium. 

Likewise, Ce + also gives complexes. For example, with sulfate ions, there is formation of the complex [Ce(S04)+]. 

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