wiz-icon
MyQuestionIcon
MyQuestionIcon
26
You visited us 26 times! Enjoying our articles? Unlock Full Access!
Question

For a given reaction of the first order, it takes 15 minutes for the concentration to drop from 0.8 M to 0.4 M. The time required for the concentration to drop from 0.1 M to 0.025 M will be:

A
15 minutes
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
60 minutes
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
30 minutes
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
7.5 minutes
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C 30 minutes
The reactant concentration drop from 0.8 M to 0.4 M i.e., 50% takes place in 15 minutes. So half life of the reaction is 15 minutes.
Rate constant:
k=0.693t12

k=0.69315=0.0462 min1
Now the time taken for the concentration to drop from 0.1 M to 0.025 M

t=2.303klog0.10.025=2.3030.0462log0.10.02530min

Hence, option (c) is correct.


flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Half Life
CHEMISTRY
Watch in App
Join BYJU'S Learning Program
CrossIcon