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For the second-order reaction 2A -> A2, the rate of formation of A2 is 10⁻⁵ M s⁻¹ when [A] = 0.01 M. The rate constant defined through the rate of disappearance of A, -d[A]/dt = k[A]², in M⁻¹ s⁻¹ is:
- 0.1
- 0.2
- 0.05
- 1.0
Correct answer: 0.2
Solution
Rate of disappearance of A = 2 x 10⁻⁵ M s⁻¹, so k = (2 x 10⁻⁵)/(0.01)² = 0.2 M⁻¹ s⁻¹.
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