The dilution of a buffer does not change the pH of the buffer. The reason for the lack of change is because the ratio of the weak acid with its conjugate base does not change. Although the overall volume of the solution increases when being diluted, it changes both the acids and the bases concentration by the same amount, thus not affecting the ratio. As for the effectiveness of the buffer, with dilution, it decreases. This is because there is less of the actual buffer and more of the water; which is susceptible to changing pH.
In the experiment, it took 8 drops of HCl in order to change the buffer solution by one pH unit. Due to the ratio of the type of acid and base, the buffer allowed for the pH to stay the same after adding multiple drops
In the experiment, it took 8 drops of HCl in order to change the buffer solution by one pH unit. Due to the ratio of the type of acid and base, the buffer allowed for the pH to stay the same after adding multiple drops