UPSC Combined Geo-Scientist, Mains · 2023 · Mains Paper II

Q12(a). Gibbs–Duhem equation

15 marks
Topic: Chemical thermodynamics and chemical equilibrium
Question only

Question

Derive Gibbs–Duhem equation in the form S dT − V dP + Σ nᵢ dμᵢ = 0.

Model answer

The free solution for 2023 answers questions 1, 2, 3, 4, 6, 8, 10, 11, 13 and 14, the ones picked in its time plan. Question 12 is answered in full in the Geo-Scientist Chemistry Paper II, 2021 to 2025 book, with every part of every paper.

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UPSC Combined Geo-Scientist (Main) Chemistry Paper II: Model Answers 2021 to 2025

All fifteen questions of each paper, with the question printed above its answer
Numericals worked from formula to result with units; graphs with labelled axes
Topic-wise weightage and a topic-wise index

Printed copy Kindle edition Read sample pages

Topic notes: chemical potential, partial molar quantities, the Gibbs–Duhem equation, fugacity and activity, with every Civil Services, IFoS and Geo-Scientist PYQ →

CoversGibbs–Duhem equationchemical potentialpartial molar quantitiesEuler theoremopen system thermodynamics

All parts of Question 12

12(a) Gibbs–Duhem equation15 marks
12(b) Ionic strength of a 3:2 electrolyte5 marks