pka of aceticacid = -logka
           Â
= -log(1.75*10^−5)
          Â
           Â
= 4.76
aceticacid + CH3COONa = buffer
pH of acidic buffer = pka + log(salt/acid)
                    Â
= 4.76 + log(0.1/0.1)
                    Â
= 4.76
           Â
pH = 4.76
         Â
CH3COOH (aq) <-----> CH3COO-(aq) + H^+(aq)
  initial 0.1
MÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
0.1 MÂ Â Â Â Â Â 0
  change  Â
x                     Â
x        x
equilibrium
0.1-x             Â
0.1+x       x
   ka =
[CH3COO-][H+]/[CH3COOH]
   1.75*10^-5 =
((0.1+X)X)/(0.1-X)
   X = 1.75*10^-5 M
percentage dissociation of CH3COOH = dissociated /
initial*100
              Â
= (1.75*10^-5)/0.1*100
             Â
= 0.0175 %