Easy INTEGER +4 / -1 PYQ · JEE Mains 2021

For a first order reaction, the ratio of the time for 75% completion of a reaction to the time for 50% completion is ____________. (Integer answer)

Answer (integer) 2

Solution

$k = {{2.303} \over t}\log {a \over {a - x}}$<br><br>$${{2.303} \over {{t_{50\% }}}}\log {{100} \over {100 - 50}} = {{2.303} \over {{t_{75\% }}}}\log {{100} \over {100 - 75}}$$<br><br>$\Rightarrow$ ${t_{75\% }} = 2{t_{50\% }}$

About this question

Subject: Chemistry · Chapter: Chemical Kinetics · Topic: Rate of Reaction

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