What will the acid always have extra?
The acidic nature of acids is due to presence of H3O+ (hydronium ) ion, when acids are dissolved in aqueous solution.
HCl + H2O(l) -----------> H3O+ (aq) + Cl- (aq)
Due to presence of H3O+ ions HCL is an acidic, more are the number of hydronium ion concentration in solution, hence more is the acidity of the acid.
pH = -log(H3O+)