Calculation of pH Value of Ammonium Acetate Solution
There is an ammonium acetate solution today, and its pH value is desired.

Ammonium acetate is a salt of weak acid (acetic acid) and weak base (ammonia water). Its ionization in water, acetate ions ($CH_3COO ^ - $) and ammonium ions ($NH_4 ^ + $) will hydrolyze.

The ionization constants of acetic acid $K_a $and ammonia water $K_b $are known.

Let the concentration of ammonium acetate be $c $. The equilibrium constant of acetate ion hydrolysis is $K_ {h1} =\ frac {K_w} {K_a} $, and the equilibrium constant of ammonium ion hydrolysis is $K_ {h2} =\ frac {K_w} {K_b} $.

Since the degree of hydrolysis of acetate ion and ammonium ion in ammonium acetate is similar, the concentration of $H ^ + $in the solution can be approximated by the following formula:

$[H ^ +] =\ sqrt {K_a\ times K_w\ div K_b} $

Substitute the known values of $K_a $, $K_b $, $K_w $into the above formula to calculate the value of $[H ^ +] $.

Then according to $pH = -\ lg [H ^ +] $, the pH value of ammonium acetate solution can be obtained. After rigorous calculation and derivation, its pH value can be obtained to illustrate the acid and alkali status of the solution.