I performed a lab experiment to Determine the solubility product of Calcium Hydroxide and after pouring the solid free supernatant to a beaker, I pipetted out 25 mL of supernatant solution and run that volume into a 25 mL standard HCl (0.1M) solution and mixed well
Then I titrated the total volume of the solution with standard NaOH solution(0.1M) using Phenolphthalein indicator according to the Lab experiment guide book.
Why we add HCl to the supernatant solution? Why we can't titarate the supernatant solution directly with NaOH?
or why we titrate Saturated Calcium Hydroxide solution directly NaOH,Rather than with HCl?