How many moles of sodium acetate are in the buffer?

Question

This is the full question:

To prepare an acetic acid/acetate buffer, a technician mixes 30.5 mL of  M acetic acid and 19.5 mL of  M sodium acetate in a 100‑mL volumetric flask and then dilutes the solution to the 100.00 mL mark. Determine the number of moles of acetic acid and the number of moles of sodium acetate in the buffer.

Answer 1

You omitted the molarity of the acetic acid and the sodium acetate. I will assume the following:

30.5 mls of 0.080 M acetic acid

19.5 mls of 0.090 M sodium acetate

moles acetic acid = 30.5 mls x 1 L / 1000 mls x 0.080 mols / L = 0.00244 mols acetic acid

moles sodium acetate = 19.5 mls x 1 L / 1000 mls x 0.09 mols / L = 0.001755 mols sodium acetate