Question

In a first order reaction, the time required for the completion of 99% is _______  times the time required for the completion of half of the reaction.

(a) 5

(b) 10

(c) 20

(d) 50

This question was addressed to me in semester exam.

This key question is from Integrated Rate Equation and Half Lives in portion Reaction Dynamics of Engineering Chemistry I

Answer 1

Correct option is (b) 10

To elaborate: In a first order reaction, the time required for the completion of 99% is ten times the time required for the completion of half of the reaction. ln [A] = -kt + ln [A0].