You prepare a buffer solution by dissolving 2.00 g each of benzoic acid, C6H5COOH and sodium benzoate, NaC6H5COO in 750.0 mL of water. What is the pH of this buffer? Assume that the solution's volume is 750.0 mL.

Answer 1

mols = grams/molar mass
and M = mols/L

Convert 2.00 g each into mols with the above formula, then use the second one to find M.
Plug these into the Henderson-Hasselbalch equation and solve for pH. Post your work if you get stuck.