Equilibrium Question 825
Question: For preparing a buffer solution of pH 6 by mixing sodium acetate and acetic acid, the ratio of the concentration of salt and acid should be $ (K_{a}={10^{-5}}) $
Options:
A) 1:10
B) 10:1
C) 100:1
D) 1:100
Show Answer
Answer:
Correct Answer: B
Solution:
$ 6=-log{10^{-5}}+log\frac{salt}{acid}=5+log\frac{salt}{acid} $
$ \log \frac{salt}{acid} $ must be1.
$ \therefore \frac{salt}{acid}=\frac{10}{1},or,10:1. $
