NEST2026ChemistryChemical Kinetics
Consider two reactions. I. A zero order reaction: X P ₁ . II. A first order reaction: Y P ₂ . Both reactions begin simultaneously with the same initial concentration ' C ', that is X₀ = Y₀ = C . It is observed that the concentrations of the reactants fall to one-third of their initial values at the same time, provided the rate constants satisfy a certain ratio. If k₀ and k₁ denote, respectively, the zero and first or
Options
- AC 3
- B3C 2 2
- CC 2
- D2C 3 3
Correct answer
D. 2C 3 3
Step-by-step solution
For the zero order reaction: [X] = [X]₀ - k₀ t C 3 = C - k₀ t k₀ t = 2C 3 t = 2C 3k₀ For the first order reaction: [Y] = [Y]₀ e^ -k₁ t C 3 = C e^ -k₁ t k₁ t = 3 t = 3 k₁ Equating the time t for both reactions: 2C 3k₀ = 3 k₁ k₀ k₁ = 2C 3 3 Answer: 2C 3 3