Question

What will be the $pH$ of $0.1\, M \,CH _{3} COONH _{4}$ ?
$K_{a}=1.8 \times 10^{-5} ; K_{b}=1.8 \times 10^{-5}$

Answer 1

$pH =\frac{1}{2}\left[ pK _{w}+ pK _{a}- pK _{b}\right]$

$\because pK _{a}= pK _{b}$

$\therefore pH =\frac{1}{2} \times pK _{w}=\frac{1}{2} \times 14=7$