please tell me if i am correct

Question

a buffer is made using HF and NaF-with a pH of 3.00. compute the ratio of the conjugate base F- to weak acid HF.
I previously found Ka of HF which is 7.2x10^-4 and the ph of HF is 3.15.

the concentration of NaF would be 1.00x10^-2 ????

and so the ratio would be 1.00 over 7.2 x 10^-2 ??

Answer 1

Use the Henderson-Hasselbalch equation.
pH = pKa + log [(base)/(acid)]
3.00 - 3.14 + log B/A
solve for the ratio of B/A. I get 0.72 but check my work.