Which order of reaction obeys the relation t1/2 = 1/Ka____________________?
Correct answer: B. Second order
- A. First order
- B. Second order
- C. Third order
- D. Zero order
Explanation
For a second-order reaction with initial concentration a, the half-life is t1/2 = 1/(k a), so the stated inverse relationship with k and concentration identifies second-order kinetics. Students may choose first order because its half-life is also discussed frequently, but first-order t1/2 = 0.693/k and does not contain the initial concentration term.
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About Order of Reaction
Reaction order shows how the rate depends on the concentration of each reactant, as expressed in the rate law. Coverage includes zero, first and second-order reactions, integrated rate equations, half-life, units of rate constants and the distinction between overall order and molecularity.
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