A student titrates HCl with 0.0125M KOH. Starting with 50.00 ml of the acid it takes 40.0 ml of base to reach equilavence point.

A. What is the concentration of the HCl?

B. What is the initial pH of the acid solution?

C. What is the pH of the reaction mixture after the addition of 20.00 ml of base?

D. What is the pH at equivlance point?

E. What is the pH after the addition of 50.00 ml of the base?

Five questions rolled into one. How much of this do you know how to do? What is it exactly that you don't understand?