Question

$pH$ of a salt of a strong base with weak acid

• A. $pH =\frac{1}{2} pK _{ w }+\frac{1}{2} pK _{ a }+\frac{1}{2} \log C$
• B. $pH =\frac{1}{2} pK _{ w }-\frac{1}{2} pK _{ a }-\frac{1}{2} \log C$
• C. $pH =\frac{1}{2} pK _{ w }+\frac{1}{2} pK _{ a }-\frac{1}{2} \log C$
• D. None of these

Answer 1

Answer: (A)

For salt of a strong base with weak acid,
$pH =\frac{1}{2} pK _{ w }+\frac{1}{2} pK _{ a } \frac{1}{2} \log C$
$ =7+\frac{1}{2} pK _{ a }+\frac{1}{2} \log C$