Question

the half life period of a 1st order reaction is 30min calculate the time required to be completed in 25% completed​

Answer 1

Answer:

For the first-order reaction, the relationship between the half-life period and the rate constant is 

k=t1/20.693=300.693=0.0231min−1.

The rate law expression is k=t2.303log(a−x)a.

Substitute values in the above expression.

0.0231=702.303log(a−x)a

log(a−x)a=0.7021

(a−x)a=5.036

aa−x=5.0361=0.2

Thus, the percentage of the reactant remaining after 70 min will be 20%.