Given E deg(Ag+/Ag) = 0.80 V, K_sp(AgI) = 1.0 x 10^-16 and 2.303RT/F = 0.0591 V at 298 K. Which statements are correct?

E deg(AgI/Ag,I-) approx -0.146 V

In 1 M KI at pH 0, metallic silver is thermodynamically oxidised by H+ (1 M) with evolution of H2 at 1 bar

In 1 M KI saturated with AgI, [Ag+] = 10^-16 M

E deg(AgI/Ag,I-) approx -0.146 V

In 1 M KI at pH 0, metallic silver is thermodynamically oxidised by H+ (1 M) with evolution of H2 at 1 bar

In 1 M KI saturated with AgI, [Ag+] = 10^-16 M

The potential of the Ag | AgI | I- electrode increases as [I-] increases

JEE Advanced levelOne or more correct optionsDifficulty 3 of 3ec108

Given $E^{\circ} (Ag X^{+} / Ag) = 0.80 V$ , $K_{s p} (AgI) = 1.0 \times 1 0^{- 16}$ and $2.303 RT / F = 0.0591 V$ at 298 K. Which statements are correct?

A $E^{\circ} (AgI / Ag, I X^{-}) \approx - 0.146 V$
BIn $1 M$ KI at pH 0, metallic silver is thermodynamically oxidised by $H X^{+}$ (1 M) with evolution of $H X_{2}$ at 1 bar
CIn $1 M$ KI saturated with AgI, $[Ag X^{+}] = 1 0^{- 16} M$
DThe potential of the $Ag ∣ AgI ∣ I X^{-}$ electrode increases as $[I X^{-}]$ increases

E^{\circ} (AgI / Ag) = 0.80 + 0.0591 lo g (1 0^{- 16}) = 0.80 - 0.946 = - 0.146 V

(A). This is below

E^{\circ} (H X^{+} / H X_{2}) = 0

, so for

2 Ag + 2 H X^{+} + 2 I X^{-} 2 AgI + H X_{2}

E_{cell}^{\circ} = 0 - (- 0.146) = + 0.146 V > 0

and the reaction is spontaneous (B).

[Ag X^{+}] = K_{s p} / [I X^{-}] = 1 0^{- 16} M

(C).

E = E^{\circ} (AgI / Ag) - 0.0591 lo g [I X^{-}]

decreases as

[I X^{-}]

increases, so (D) is wrong.