NTA Abhyas JEE Main2020ChemistryElectrochemistryPractice
Calculate Δ G o for the following cell reaction Zn s + Ag 2 O s + H 2 O l → Zn 2 + aq + 2 Ag s + 2 OH − aq E A g + / A g 0 = + 0.80 V a n d E Z n + 2 / Z n 0 = - 0.76 V ,F=96500 (Given: K sp of AgOH = 2 × 10 − 8 )
Options
- A- 305 k J / m o l
- B212 k J / m o l
- C305 k J / m o l
- D301 k J / m o l
Correct answer
B. 212 k J / m o l
Step-by-step solution
Calculation for E O H - A g 2 O A g - Reduction [ 2 A g + + 2 e - → 2 A g s , ∆ G 1 o = - 2 × F × E o A g + | A g Ionisation [ A g 2 O + H 2 O l → 2 A g + + 2 O H - ∆ G 2 o = - 2.303 R T l o g k s p 2 Net A g 2 O + H 2 O l + 2 e - → 2 A g s + 2 O H - , ∆ G 3 o = - 2 × F × E O H - A g 2 O A g o ∆ G 3 o = ∆ G 1 o + ∆ G 2 o + 2 × F × E O H - A g 2 O A g o = + 2 × F × E o A g + | A g + 2.303 R T l o g k s p 2 2 F E O H - A g 2 O A g o = E o A g + | A g + 0.06 2 × 2 log k s p = 0.8 + 0.06 log 2 × 10 - 8 = 0.8 + 0.06