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COMEDK202510 May 2025Morning ShiftChemistryChemical KineticsActual

Two statements, One Assertion (A) and the other Reason (R) are given. Choose the right option. Assertion: The rate constant ( k ) for a chemical reaction gets nearly doubled for a 10^ rise in temperature. Reason: The number of bimolecular collisions between reactant molecules increase with increase in temperature

Options

  1. AA is wrong but R is correct.
  2. BBoth A and R are correct but R is not the correct explanation of A .
  3. CBoth A and R are correct and R is the correct explanation of A .
  4. DA is correct but R is wrong.

Correct answer

B. Both A and R are correct but R is not the correct explanation of A .

Step-by-step solution

The rate constant k of a reaction is given by the Arrhenius equation k = A e^ -E_a / RT . For most reactions, a 10^ C rise in temperature leads to a doubling or tripling of the rate constant. This is primarily due to the increase in the fraction of molecules possessing energy greater than or equal to the activation energy E_a , which is represented by the term e^ -E_a / RT . The number of bimolecular collisions between reactant molecules does increase with an increase in temperature because the average kinetic ener

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