A) In 8 minutes
B) In 12 minutes
C) In 16 minutes
D) In 20 minutes
Correct Answer: B
Solution :
20 gm substance reduces to 10 gm (i.e. becomes half in 4 min. So \[{{T}_{1/2}}=4\,\min \]. Again \[M={{M}_{0}}{{\left( \frac{1}{2} \right)}^{t/{{T}_{1/2}}}}\] Þ \[10=80\,{{\left( \frac{1}{2} \right)}^{t/4}}\]Þ\[\frac{1}{8}={{\left( \frac{1}{2} \right)}^{3}}={{\left( \frac{1}{2} \right)}^{t/4}}\]Þ t = 12 min.You need to login to perform this action.
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