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Most Important Selected Qs for JEE AdvancedChemistryChemical Kinetics

Consider an endothermic reaction A K _ b K ₁ ~B ~K _ f and K _ b are the forward and the backward rate constant at temperature T ₁ . The temperature is decreased from T₁ to T₂ and the rate constants are K_f^ and K_b^ for the forward and the backward reaction respectively at this temperature. Select the incorrect relation.

Options

  1. AK _ f K _ f ^ and K _ b K _ b ^
  2. BK _f^ K _ f K _ b ^ K _ b
  3. CK _ f - K _ f ^ K _ f K _ b - K _ b ^ K _ b
  4. DK _ f - K _ f ^ K _ f K _ b - K _ b ^ K _ b

Correct answer

D. K _ f - K _ f ^ K _ f K _ b - K _ b ^ K _ b

Step-by-step solution

As temperature decreases rate constant decreases. So, K _ f ^ K _ f and K _ b ^ K _ b . The rate constant with greater activation energy is more sensitive towards temperature So, % decrease in K _ f will be greater than % decrease in K _ b

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