If the half life of a first order reaction is 6.93 minutes then the time required for completion of 99% of the reaction will be minutes. (Given : log 2 = 0.3010)
Answer
46
Solution
For a first order reaction, t1/2 = 0.693k
⇒ k = 0.6936.93 = 0.1 min-1
For 99% completion, [R] = [R]0100:
t = 2.303k [R]0[R] = 2.3030.1 100
= 23.03 2 = 46.06 min ≈ 46 min
Answer: 46