The EMF of the cell Cr | Cr^3+ (0.002 M) || Cr^3+ (0.2 M) | Cr at 298 K is (take 2.303RT/F = 0.0591 V)

JEE Main levelSingle correct optionDifficulty 2 of 3ec093

The EMF of the cell $Cr ∣ Cr X^{3 +} (0.002 M) ∣∣ Cr X^{3 +} (0.2 M) ∣ Cr$ at 298 K is (take $2.303 RT / F = 0.0591 V$ )

Concentration cell with

n = 3

for

Cr X^{3 +} / Cr

E = \frac{0.0591}{3} lo g \frac{0.2}{0.002} = 0.0197 \times 2 = 0.0394 V = 39.4 mV

. Using

n = 1

gives 118.2 mV and

n = 2

gives 59.1 mV.