The standard reduction potential of Cu2+ / Cu and Ag+/Ag electrodes are 0.337 and 0.799 V respectively. Construct a galvanic cell using these electrodes so that its standard emf is positive. For what concentration of Ag+ will the emf of the cell, at 25° C, be zero if the concentration of Cu2+ is 0.01 M?

Question

The standard reduction potential of Cu2+ / Cu and Ag+/Ag electrodes are 0.337 and 0.799 V respectively. Construct a galvanic cell using these electrodes so that its standard emf is positive. For what concentration of Ag+ will the emf of the cell, at 25° C, be zero if the concentration of Cu2+ is 0.01 M? (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

The galvanic cell is: Cu| Cu2+|| Ag+ | Ag Cell reaction: Cu + 2Ag+ leftharpoons Cu2+ + 2Ag; E° = 0.462 V E = 0 + 0.462 - (0.0592/2) log ((0.01)/[Ag+]2) ⇒ [Ag+] = 1.57 × 10-9 M

The galvanic cell is : Cu∣Cu2+∣∣Ag+∣Ag Cell reaction : Cu+2Ag+⇌Cu2++2Ag;E∘=0.462V E=0+0.462−20.0592​log[Ag+]2(0.01)​ ⇒[Ag+]=1.57×10−9M

The galvanic cell is : $C u ∣ C u^{2 +} ∣∣ A g^{+} ∣ A g$
Cell reaction : $C u + 2 A g^{+} ⇌ C u^{2 +} + 2 A g; E^{\circ} = 0.462 V$
$E = 0 + 0.462 - \frac{0.0592}{2} lo g \frac{( 0.01 )}{[ A g ^{+} ] ^{2}}$
$\Rightarrow [A g^{+}] = 1.57 \times 1 0^{- 9} M$