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JEE Main20265 April 2026Morning ShiftChemistryChemical KineticsActual

If the half life of a first order reaction is 6.93 minutes then the time required for completion of 99 % of the reaction will be _____ minutes. (Given : 2 = 0.3010 )

Correct answer

0

Step-by-step solution

For a first-order reaction, the rate constant k is given by: k = 2.303 2 t_ 1/2 Using the standard approximation 2.303 2 0.693 : k = 0.693 6.93 = 0.1 min ⁻¹ The time required for 99 % completion of the reaction is given by the integrated rate law: t = 2.303 k ( a a - x ) Here, the initial concentration a = 100 and the amount reacted x = 99 , so a - x = 1 . t = 2.303 0.1 ( 100 1 ) t = 23.03 (10^2) t = 23.03 2 = 46.06 minutes Answer: 46.06

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