Calculate the pH of the buffere prepared if 40.0 mL of .2M NaOH is added. The previous buffer is made from HF an NaF... assume all necessary information is known about this buffer. Print an equation that shows how the NaOH is consumed by the buffereing agents. Which side does the reaction favor? Why sodium ion is ignored?

You posted only part of the problem. I suggest you make a new post; this time write all of the information.