Q13(a). Consecutive first-order reactions: [A], [B] and [C] against time
For the consecutive first-order reaction A →(k₁) B →(k₂) C, [A] = [A]₀, [B] = 0 and [C] = 0 at time t = 0. Derive the expressions of [A], [B] and [C] as a function of time. Provide a general graphical representation of variation in concentration of [A], [B] and [C] with respect to time.
Answer in brief
[A] = [A]₀e−k₁t; [B] = k₁[A]₀(e−k₁t − e−k₂t)/(k₂ − k₁); [C] = [A]₀[1 + (k₁e−k₂t − k₂e−k₁t)/(k₂ − k₁)].
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Coversconsecutive reactionsfirst-order kineticsreactive intermediatetmaxsteady-state approximationradioactive decay chain
All parts of Question 13
- 13(a) Consecutive first-order reactions: [A], [B] and [C] against time15 marks
- 13(b) Time at which [B] is a maximum5 marks