NTA Abhyas NEET2020ChemistryElectrochemistryPractice
On the basis of information available for the reaction. 4 3 Al + O 2 → 2 3 Al 2 O 3 ; ΔG = –827 kJ/mol of O 2 The minimum emf required to carry out an electrolysis of A l 2 O 3 is: Given: One Faraday = 96500 C
Options
- A2.14 V
- B4.28 V
- C6.42 V
- D8.56 V
Correct answer
A. 2.14 V
Step-by-step solution
A l → A l 3 + + 3 e – 4 3 mol   Al ≡ 4 3   ×   3   mol   e − ≡ 4   mol   e – n = 4 Δ G = – n F E – 827 × 1000 = – 4 × 96500 × E E = 2.14   V