[tamubsa]

If 2.75 g of NaCH3CHOHCO2, sodium lactate, is added to 5.00 x 102 mL lactic acid, what is the pH
of the resulting buffer solution? I am having a lot of trouble figuring out how to solve this problem. Normally with buffers I would use the Henderson-Hasselbalch equation, but you aren't given any information except for the volume about lactic acid. Don't I at least need the number of moles of the acid and conjugate base to find the pH?

[Borek]

As worded question is definitely missing some information.