JEE Main2014ChemistryElectrochemistryActual
A current of 10 . 0 A flows for 2 . 00 h through an electrolytic cell containing a molten salt of metal X . This results in the decomposition of 0 . 250 mol of metal X at the cathode. The oxidation state of X in the molten salt is: F = 96 , 500 C
Options
- A1 +
- B4 +
- C3 +
- D2 +
Correct answer
C. 3 +
Step-by-step solution
Quantity of Electricity = 1 0 × 3 6 0 0 × 2 9 6 5 0 0 = 0 .746 ≈ 0 .75 F . If oxidation state is n + for 1   mol deposition of a metal: Electricity = nF (Faradays) For 0 . 250   mol = 0.250   nF ∴   0.250   nF = 0.75   F n = 3