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Most Important Selected Qs for JEE AdvancedChemistryChemical Kinetics

The ratio t_ 1 / 2 : t_ 3 / 4 of a reaction having order equal to ' n ' (n 1) is ( t _ 3 / 4 is the time required for concentration of reactant to drop to 3 4 times its initial value)

Options

  1. ADependent on initial concentration [A₀ ] and equal to 2^ n-1 [A₀ ]^ n-1 ( 3 4 )^ n-1
  2. BDependent on initial concentration [A₀ ] and equal to 2^ n-1 [A₀ ]^ n-1 -1 ( 4 3 )^ n-1 [A₀ ]^ n-1 -1
  3. CIndependent of initial concentration and equal to 2^ n-1 -1 ( 4 3 )^ n-1 -1
  4. DIndependent of initial concentration and equal to n 2^ n-1 -1 n ( 4 3 )^ n-1 -1

Correct answer

C. Independent of initial concentration and equal to 2^ n-1 -1 ( 4 3 )^ n-1 -1

Step-by-step solution

aligned & K _ n t = 1 ( n -1) [ 1 ~A _ t ^ n-1 - 1 ~A ₀^ n -1 ] & K _ n t _ 1 / 2 = 1 ( n -1) [ 2^ n-1 ~A ₀ - 1 ~A ₀ ] & K _ n t _ 3 / 4 = 1 ( n -1) [ ( 4 3 )^ n-1 ~A ₀ - 1 ~A ₀ ] & t _ 1 / 2 t _ 3 / 4 = 2^ n-1 -1 ( 4 3 )^ n-1 -1 aligned

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