For 3rd order reactions, the half-life is:
Correct answer: A. Inversely proportional to the square of the concentration
- A. Inversely proportional to the square of the concentration
- B. Directly proportional to the cube of the concentration
- C. Inversely proportional to the concentration
- D. Directly proportional to the concentration
Explanation
The half-life of any order reaction is inversely proportional to the initial concentration raised to the power one less than the order of that reaction. [t1/2 ∝ (1/a)n-1] Where, 't1/2' represents the half-life 'a' represents the initial concentration of reactants 'n' represents the order of reaction As a(n-1) = a2 So, for 3rd-order reactions, the half-life is inversely proportional to the square of the concentration.
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Reaction kinetics relates reaction rate to concentration, temperature, surface area and catalysts. Questions cover rate laws, reaction order, rate constants, activation energy and the activated complex, including how a catalyst lowers the activation energy without changing the overall energy change or equilibrium position.
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