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JEE Main202310 Apr 2023Morning ShiftChemistryChemical KineticsActual

A molecule undergoes two independent first order reactions whose respective half lives are 12 min and 3 min . If both the reactions are occurring then the time taken for the 50 % consumption of the reactant is ______ min . (Nearest integer)

Correct answer

0

Step-by-step solution

For parallel reaction When adding the rate constants of the two reactions, we need to use the formula for combining rate constants of two reactions in parallel, which is: k = k 1 + k 2 where k 1 and k 2 are the rate constants of the individual reactions. In this case, the half-lives of the two reactions are 12 min and 3 min, respectively. The rate constants of the two reactions can be calculated using the formula for half-life of a first-order reaction: 1 t 1 / 2 = 1 12 + 1 3 = 5 12 Net t 1 / 2 = 12 5 = 2 . 4 &#160

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