Which order reaction obey the expression t1/2 = 1/Ka
Correct answer: B. Second
- A. First
- B. Second
- C. Third
- D. Zero
Explanation
For a second-order reaction, the half-life is inversely proportional to the initial concentration of the reactant, Hence the correct answer is B. For option A, the Half-life of a first-order reaction is inversely proportional to the concentration of the reactant. For option C, the Half-life of a third-order reaction is inversely proportional to the square of the initial concentration of the reactant. Thus, it is incorrect. For Option D, the Half-life is directly proportional to the initial concentration of reactants.
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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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