A reaction has a half life of 1 min. The time required for 99.9% completion of the reaction is _________ min. (Round off to the Nearest Integer). [Use : ln 2 = 0.69; ln 10 = 2.3]
Answer (integer)
10
Solution
Given t<sub>1/2</sub> = 1 min<br><br>$\therefore$ $K = {{\ln 2} \over {{t_{1/2}}}} = {{\ln 2} \over 1}$<br><br>From formula we know,<br><br>$Kt = \ln \left( {{{100} \over {100 - x}}} \right)$<br><br>$$ \Rightarrow {{\ln 2} \over 1} = {1 \over t}\ln \left( {{{100} \over {0.1}}} \right)$$<br><br>$\Rightarrow 0.3 = {1 \over t}\ln \left( {{{10}^3}} \right)$<br><br>$\Rightarrow 0.3 = {1 \over t} \times 3$<br><br>$\Rightarrow t = 10$ min
About this question
Subject: Chemistry · Chapter: Chemical Kinetics · Topic: Rate of Reaction
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