You have 0.500 l of an 0.250 m acetate buffer solution (i. e. [hc₂h₃o₂] + [c₂h₃o₂⁻] = 0.250 m) at ph 3.50. how many ml of 1.000 m naoh must you add in order to change the ph to 5.25? acetic acid has a pka of 4.74.

Explanation:

Relation between pH and is as follows.

            pH =

Hence, total moles of acetate is calculated as follows.

           = 0.125 M

                 =

                 = 0.0575

Let us assume that there are x moles of acid. Hence, moles of B are as follows.

                 B = (0.125 - x) moles

      = 0.0575

                  x = 0.118 moles

Now, we will calculate the concentration as follows.

           5.25 = 4.74 +

                        = 3.236

                     x =

                         = 0.0295 moles

Therefore, moles of NaOH needed to add are as follows.

        = (0.118 - 0.0295) moles

          = 0.0885 moles

                            =

                            = 88.5 ml

Thus, we can conclude that there is 88.5 ml of 1.000 M NaOH must you add in order to change the pH to 5.25.