The gaseous first order reaction A -> B + C was found to have a half life of 20 s when the initial pressure of A was 2 atm. When the initial pressure of A is increased to 4 atm, the half life is:
Correct answer: B. 20 s
- A. 10 s
- B. 20 s
- C. 40 s
- D. 400 s
Explanation
b) 20 s:This option suggests that the half-life of the reaction would remain the same at 20 s when the initial pressure of A is increased to 4 atm. It is possible for the half-life to remain constant, especially if the rate constant and reaction conditions remain unchanged.
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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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