16.Which order of reaction obeys the relation t1/2= 1/Ka
Correct answer: B. (b) Second order
- A. (a) First order
- B. (b) Second order
- C. (c) Third order
- D. (d) Zero order
Explanation
The relation t1/2 = 1/Ka correctly points towards a (b) Second order reaction. Here's why:Explanation:t1/2 represents the half-life of the reaction, which is the time taken for the reactant concentration to decrease by half of its initial value.Ka can be interpreted as the apparent rate constant for the second-order reaction. It combines the actual rate constant (k) with the initial concentration of the reactant ([A]0): Ka = k * [A]0.With this understanding, let's analyze the given equation:t1/2 = 1/KaSubstitute Ka with its definition: t1/2 = 1/(k * [A]0)Rearrange the equation: t1/2 = [A]0/k
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