A Galvanic cell is constructed with Ag ⁺ Ag and Fe ³⁺ Fe ²⁺ electrodes. Find the concentration of Ag ⁺ at which the emf of the cell is zero at equimolar concentrations of Fe ²⁺ and Fe ³⁺ . (E_ Ag ^ Ag ^ =0.80 ~V and E _ Fe ³⁺¹ Fe ²⁺ ^ =0.77 ~V ) (mark the answer in M)

Step-by-step solution

As E ^ for silver electrode is more positive, the cell may be represented as aligned & Fe ²⁺, Fe ³⁺ | Ag ⁺, Ag ₁ E _ cell ^ =0.80-0.77=0.03 ~V & E _ cell =0.03- 0.0591 1 [ Fe ³⁺ ] [ Fe ²⁺ ] [ Ag ⁺ ] & E _ cell =0.03+ 0.0591 1 [ Ag ⁺ ] [ Fe ³⁺ ]= [ Fe ²⁺ ] & 0=0.03+ 0.0591 1 [ Ag ⁺ ] [ Ag ⁺ ]=0.3121 M aligned