The half life of a certain first order reaction is 60 minutes. How long will it take for 80% reaction to occur ?

Question

The half life of a certain first order reaction is 60 minutes. How long will it take for 80% reaction to occur ? (A) 139.39 min (B) 19.9 min (C) 199.39 hrs (D) 40 min

Tardigrade Admin · Accepted Answer

k=(2.303/t)log ((a/a-x)) (0.693/60)=(2.303/t)log ((100/100-80)) t=199.39 min

Q. The half life of a certain first order reaction is 60 minutes. How long will it take for 80% reaction to occur ?

139.39 min

19.9 min

199.39 hrs

40 min

$k = \frac{2.303}{t} l o g (\frac{a}{a - x})$
$\frac{0.693}{60} = \frac{2.303}{t} l o g (\frac{100}{100 - 80})$
$t = 199.39 min$

Q. The half life of a certain first order reaction is 60 minutes. How long will it take for 80% reaction to occur ?

139.39 min

19.9 min

199.39 hrs

40 min

k=t2.303​log(a−xa​) 600.693​=t2.303​log(100−80100​) t=199.39min

$k = \frac{2.303}{t} l o g (\frac{a}{a - x})$
$\frac{0.693}{60} = \frac{2.303}{t} l o g (\frac{100}{100 - 80})$
$t = 199.39 min$