UPSC Combined Geo-Scientist, Mains · 2023 · Mains Paper II
Q14(b). Spontaneous reaction: cell, E°cell and K at 298 K
Question
Among the above, identify the spontaneous reaction, if any, and write down the overall cell reaction. Calculate its E°cell and the equilibrium constant of the overall cell reaction at 298 K.
Answer in brief
Reaction (iii): 2Fe³⁺ + Sn²⁺ → 2Fe²⁺ + Sn⁴⁺; E°cell = 0.617 V; K = 7.4 × 10²⁰ at 298 K.
Part of VKC Basic
Read the key points and the full model answer with VKC Basic
VKC Basic (₹999 for 6 months) opens every solved answer, the notes, the handbook and the daily answer archive. Every Mains test series includes it.
The full model answer
As written for the answer booklet: the diagram carries the working, the lines stay short. Read here only; it is not offered as a download.
The handwritten model answer pages open with the VKC plan.
Coversgalvanic cellstandard cell potentialequilibrium constant from emfΔG° = −RT ln KFe3+ Sn2+ reaction
All parts of Question 14
- 14(a) Which pairs of Fe³⁺/Fe²⁺ and Sn⁴⁺/Sn²⁺ react10 marks
- 14(b) Spontaneous reaction: cell, E°cell and K at 298 K10 marks