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MHT CET202521 Apr 2025Morning ShiftChemistryChemical KineticsActual

What is the order and molecularity respectively for the elementary reaction given below? O _ 3( ~g )+ O _ ( g ) 2 O _ 2( ~g ) if r = k [ O ₃ ][ O ]

Options

  1. A2^ nd and 1
  2. B1^ st and 2
  3. C2^ nd and 2
  4. D1^ st and 1

Correct answer

C. 2^ nd and 2

Step-by-step solution

Order and molecularity are determined for the elementary reaction O _ 3(g) + O _ (g) 2 O _ 2(g) . The experimentally determined rate law is r = k[ O ₃][ O ] , indicating the reaction is second-order overall. As an elementary reaction, molecularity corresponds to the number of reactant particles: one O ₃ molecule and one O atom, giving bimolecular behavior with molecularity 2. The order is 2 and molecularity is 2, matching option C. Final answer: C

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