question_answer

The standard reduction potential \[E{}^\circ \] for the half reactions are as                 \[Zn\xrightarrow{{}}Z{{n}^{++}}+2{{e}^{-}},\,\,E{}^\circ =0.76V\]                 \[Cu\xrightarrow{{}}C{{u}^{++}}+2{{e}^{-}},\,\,E{}^\circ =0.34V\] The e.m.f. for the cell reaction                 \[Zn+C{{u}^{2+}}\xrightarrow{{}}Z{{n}^{2+}}+Cu\]

A) \[0.42V\]                            

B) \[-0.42V\]

C) \[-1.1V\]                             

D) \[1.1V\]