A buffer solution is prepared by mixing 50.0 mL of 0.022 M C6H5COOH and 20.0 mL of 0.032 MNaC6H5CO2. (a) What is the of the buffer solution? (b) What are the pH and the change in pH after the addition of 0.054 mmol HCl to the buffer solution? (c) What would be the pH and the pH change after the addition of 10.0 mL of 0.054 M HCl to the original buffer solution?