Question -
A first order reaction is 60% complete in 20 minutes. How long will the reaction take to be 84% complete?
Options:
A .  76 mins
B .  54 mins
C .  68 mins
D .  40 mins
Answer: Option D : D If a reaction is 60% complete, 40% remains and if it is 84% complete, 16% remains. For a first order reaction: k=2.30320log10040=2.303tlog10016
Submit Your Solution hear: