For 3rd order reaction the hhalf life is inversely proportional to initial concentration of reactants__________________?
Correct answer: B. Square
- A. Single
- B. Square
- C. Cube
- D. Raise to power four
Explanation
For a single-reactant third-order reaction, the half-life varies inversely with the square of the initial reactant concentration, written as t1/2 proportional to 1/[A]0^2. Therefore, doubling the initial concentration makes the half-life one-fourth as large. Students may choose c by matching the power of the reaction order directly, but the half-life relation has the square of the concentration in the denominator for a third-order reaction.
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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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