[govibe]

Can anyone help me with this question? I have a lot of trouble with these weak acid strong base titrations

A sample of an ionic compound NaA, where A- is the anion of a weak acid, was dissolved in enough water to make 100.0 mL of solution and was then titrated with 0.119 M HCl. After 500.0 mL of HCl was added, the pH was measured and found to be 5.98. The experimenter found that 1.00 L of 0.119 M HCl was required to reach the stoichiometric point of the titration.

A) What is the Kb value for A-?

B) Calculate the pH of the solution at the stoichiometric point of the titration.

I'm totally lost...

[Borek]

50% titration, [HA] = [A^-], Henderson-Hasselbalch equation.