CH3COOH⇌CH3COO−+H+   C - x     x  x CH3COONa→CH3COO−+Na+   0.2 M    0.2 M  0.2M [CH3COOH]=C−x≈0.1M {acetic acid is a weal acid so, dissociation is minimum. [CH3COO−]=0.2+x≈0.2M {acetic acid is a weal acid so, dissociation is minimum. ∴[H+]=