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JEE MainChemistryChemical Kinetics

For a first order reaction, the time required for x % completion is exactly twice the time required for 90 % completion. The value of x is ________.

Correct answer

99

Step-by-step solution

For a first order reaction, the integrated rate law is: t = 2.303 k 100 100 - completion % Given that t_ x % = 2 t_ 90 % 2.303 k 100 100 - x = 2 2.303 k 100 100 - 90 100 100 - x = 2 10 100 100 - x = 100 100 100 - x = 100 100 - x = 1 x = 99 Answer: 99

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