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NTA Abhyas JEE Main2020ChemistryChemical KineticsPractice

For a first order reaction, the half-life is 10 mins . How much time in minutes will it take to reduce the concentration of reactant to 25 % of its original concentration?

Correct answer

20

Step-by-step solution

It takes two half-lives to reduce the concentration of reactant to 25 % of its original concentration. Hence, total time taken = 10 + 10 = 20 minutes.

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