Hi !! i am new to these forums.. so i just want to ask whether i am posting my query in the correct forum?? I have a doubt regarding this weak acid - weak base buffer. When the moles of Acid > Base, We use the formula pH = pka + log10 ([salt]/[acid]) to calculate the pH of the Acidic Buffer formed. Actually, in the derivation of this formula for calculating pH of an acidic buffer.. we assume 100% dissociation of salt.. But here, the Weak acid- Weak base salt formed does not dissociate to full extent. Kindly explain to me why we are using this formula although the salt doesn't dissociate completely.