wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

A certain buffer contains a weak base AOH and its conjugate acid (A+) at 25C.
The concentration of A+ ions is twice the concentration of AOH.
Calculate the pH of the buffer solution.
(Given base dissociation constant for AOH is Kb=105)

A
8.7
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
4.3
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
5.3
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
9.7
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is A 8.7
This is basic buffer formed by A+ and a weak base AOH.
Let the concentration of AOH= x M
Then, concentration of A+=(2×x) M
pKb=log(Kb)pKb=log(105)pKb=5

pOH of basic buffer formed is given by
pOH=pKb+log([A+][AOH])pOH=5+log(2xx)pOH=5+log(2)=5+0.3=5.3pH=14pOH=145.3pH=8.7

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