Chemical Kinetics Question 20
Question: In the first order reaction, the concentration of the reactant is reduced to 25% in one hour. The half life period of the reaction is [DCE 2004]
Options:
A) 2 hours
B) 4 hours
C) 30 min
D) 15 min
Show Answer
Answer:
Correct Answer: C
Solution:
$ K=\frac{2.303}{1\ hr}\log \frac{100}{25}=\frac{2.303}{t}\log \frac{100}{25} $ $ \therefore \ \ \log 4=\frac{1}{2}\log 2 $ $ \therefore \ \ 2\log 2=\frac{1}{t}\log 2 $ ; $ t=\frac{1}{2} $ hr.
BETA
