Hello!
To solve this problem we need to know the value of pKa for HC₂H₃O₂ (Acetic Acid) which is 4,76. Now we can apply the Henderson-Hasselbach equation, as follows (assuming that HC₂H₃O₂ concentration is 0,22M):
[tex]pH=pKa + log ( \frac{KC_2H_3O_2}{HC_2H_3O_2} )=4,76 + log ( \frac{0,122M}{0,22M} )=4,50[/tex]
So, the pH for this buffer solution of HC₂H₃O₂ and KC₂H₃O₂ is 4,50
Have a nice day!
