Answer: 3.
- A 1
- B 2
- C 3
- D 4
Correct answer: C. 3
Explanation: Molecularity = total reactant molecules in the elementary step = 2 (NO) + 1 (O₂) = 3.
First-order decay curve: concentration halves every t½, and that half-life is constant - a defining test for first-order kinetics.
Concept context
Study the speed of reactions and what affects it: concentration, temperature, and catalysts. Covers rate law, order of reaction, the Arrhenius equation, and reaction mechanisms step by step.