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JEE Main 202325 JanuaryMorning Shift
Exam
JEE Main
Year
2023
Date
25 January
Shift
Morning Shift
Subject
Chemistry
Chapter
Chemical Kinetics

JEE Main 2023 · 25 January · Morning Shift · Chemistry · Chemical Kinetics

For the first order reaction A → B the half life is 30min . The...

For the first order reaction A→BA \to B the half life is 30min30min. The time taken for 7575 % completion of the reaction is mm. (Nearest integer)

Given : log⁡2=0.3010\log 2 = 0 . 3010

log⁡3=0.4771\log 3 = 0 . 4771

log⁡5=0.6989\log 5 = 0 . 6989

Correct answer

0

Step-by-step solution

{t}_{1/2} = {T}_{50 %} = 30min

For first order reaction, from the relation between half lives:

\dfrac{2 . 303}{{t}_{50 %}}log\dfrac{100}{50} = \dfrac{2 . 303}{{t}_{75 %}}log\dfrac{100}{25}
{T}_{75 %} = 2{t}_{1/2} = 30 \times 2 = 60min

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