Question

SICUIT AI IWC =V.uss aun Example 23. The half life of a first order reaction is 60 min. How long will it take to consume 90% of the reactant?

JEE/Engineering Exams

Chemistry

Solution

4.0 (1 ratings)

( t_{1 / 2}=60 mathrm{min} ) Half life period ( =t_{1 / 2}=frac{0.693}{k} ) [ begin{array}{c} k=text { rate constant } 60=frac{0.693}{k} k=0.01155 mathrm{min} end{array} ] ( k=frac{2 cdot 303}{t} log left[frac{left.a_{0}right]}{[a]}- ) Inition right. After consuming 90"/ final conc. Dill be ( 10^{circ}(cdot ) of initial conc. Initial ( operatorname{con} c=x ) Find ( operatorname{con} c cdot i 8 cdot 10^{circ} cdot 0 . f x=frac{10}{100} x=0.1 x ) ( frac{text { Initiol } cos c}{text { Find } operatorname{conc}}=frac{x}{0.1 x}=10 ) ( 0.01155=frac{2.303}{t} log (10) ) ( 199 cdot 4 ) minuts [ t=1 ]