ElectrochemistryMedium
Question
Match List I with List II.
| List I (Conversion) | List II(Number of Faraday required) |
|---|---|
| A. 1 mol of $H_{2}O$ to $O_{2}$ | I. 3F |
| B. 1 mol of ${MnO}_{4}^{-}$to ${Mn}^{2 +}$ | II. 2 F |
| C. $\ 1.5\text{ }mol$ of Ca from molten ${CaCl}_{2}$ | III. 1F |
| D. 1 mol of FeO to ${Fe}_{2}O_{3}$ | IV. 5 F |
Choose the correct answer from the options given below:
Options
A.A-II, B-III, C-I, D-IV
B.A-III, B-IV, C-II, D-I
C.A-II, B-IV, C-I, D-III
D.A-III, B-IV, C-I, D-II
Solution
Sol. [Key Concept: Faraday requirements from electron counts]
A: 2H₂O → O₂ + 4H⁺ + 4e⁻, so oxidation of 1 mol H₂O requires 2F (A–II).
B: Mn changes from +7 to +2, requiring 5 mol electrons per mol MnO₄⁻,
hence 5F (B–IV).
C: Ca²⁺ + 2e⁻ → Ca, so 1.5 mol Ca requires 3F (C–I).
D: Fe changes from +2 in FeO to +3 in Fe₂O₃, so each mole FeO corresponds to 1F (D–III). Hence, option (3).
Create a free account to view solution
View Solution FreeMore Electrochemistry Questions
Resistance of a conductivity cell filled with a solution of an electrolyte of concentration 0.1 M is 100 Ω. The con...Lactic acid, HC3H5O3, produced in 1 g sample of muscle tissue was titrated using phenolphthalein as indicator against OH...Fe is reacted with 1.0 M HCl. Eo for Fe / Fe2+ = + 0.34 V. The correct observation(s) regarding this reaction is/are :...During discharge of a lead storage cell the density of sulphuric acid in the cell :...A hydrogen electrode placed in a buffer solution of CH3COONa and CH3COOH in the ratio’s x:y and y:x has electrode potent...