What happens when some alkali is added to a buffer solution?

The dissociation of the weak acid ‘HA’ would be shown as:HA (aq) ⇌ H⁺ (aq) + A^– (aq)Adding alkali will add OH^- ions to the solution. These will react with the H⁺ ions present in the solution, producing water (H₂O). As a result, the concentration of H⁺ ions will decrease. The system will react to oppose this change, so the position of equilibrium will move towards the side with the H⁺. Therefore, the position of equilibrium will move to the right (product side). In order to replace the lost H⁺ ions, some HA molecules will dissociate forming A^- ions in the process. This means the fall in H⁺ concentration is resisted and the pH of the buffer solution remains fairly constant.