JEE Advanced 2025 Paper 1, Chemistry Section 3 Q1: Electrochemical Cell And Nernst Equation

Balanced half-reaction:

${\text{Cr}}_2{\text{O}}_7^{2-}+14{\text{H}}^{+}+6e^{-}\to 2{\text{Cr}}^{3+}+7{\text{H}}_2\text{O}$

So 6 mol of electrons produce 2 mol of Cr${}^{3+}$; per mole of Cr${}^{3+}$, 3 mol of electrons (3 F) are needed.

Charge required: $Q=3\times 96500=289500$ C.

Time: $t=48.25\text{ min}\times 60=2895$ s.

Current: $I=\frac{Q}{t}=\frac{289500}{2895}=100$ A.

$\therefore I=100.00$ A.