JEE Main201910 Jan 2019Evening ShiftChemistryElectrochemistryActual
In the cell, Pt s H 2 g , 1 bar HCl aq AgCl s Ag s Pt s , the cell potential is 0 .92 V when a 10 - 6 molar HCl solution is used. The standard electrode potential of Ag | AgCl | Cl - electrode is: (Given, 2 .303 RT F = 0 .06 V at 298 K )
Options
- A0 .76   V
- B0 .20   V
- C0 .40   V
- D0 .94   V
Correct answer
B. 0 .20   V
Step-by-step solution
A : 1 2 H 2 g → H +   aq . + e - ;   E o = 0 .0   V C   : AgCl   s + e - → Ag   s + Cl - ;   E o = xV E cell = E cell o - 0 .06 1 log ⁡ H + Cl - 0 .92 = x - 0 . 06 1 log ⁡ 10 - 12 0 .92 = x + 0 . 72 x = 0 .92 - 0 .72 = 0 . 2 V