Q8(c)(i). Equilibrium and relaxation of an isomerisation
For a hypothetical isomerization that is first order in both directions with kf = 17.7 min⁻¹ and kr = 32.2 min⁻¹, find the equilibrium composition if the initial concentration of A is 0.150 mol L⁻¹ and the initial concentration of B is zero. Find the half-life and relaxation time.
Model answer
The free solution for 2022 answers questions 1, 2, 4, 5 and 6, the ones picked in its time plan. Question 8 is answered in full in the IFoS Chemistry Paper I, 2021 to 2025 book, with every part of every paper.
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UPSC Indian Forest Service (Main) Chemistry Paper I: Model Answers 2021 to 2025
- All eight questions of each paper, with the question printed above its answer
- Physical chemistry numericals worked with units; inorganic structures drawn
- Topic-wise weightage and a topic-wise index
Coversreversible first-order reactionrelaxation timeequilibrium compositionisomerisation kineticshalf-life
All parts of Question 8
- 8(a) Cooperativity and the Bohr effect10 marks
- 8(b)(i) Sodium solutions in liquid ammonia10 marks
- 8(b)(ii) Reducing reactions of sodium–ammonia5 marks
- 8(c)(i) Equilibrium and relaxation of an isomerisation10 marks
- 8(c)(ii) Zero or negative activation energy5 marks