Determine the ph of a buffer solution comprised of a 1.41 m hf and 0.623 m naf. the ka of hf = 7.20 x 10-4

we are going to use H-H equation:

PH = Pka + log[conjugate base]/[weak acid]

 when we have here the conjugate base is NaF

and the weak acid is HF.

 so, we are going to use the Ka value to get the value of Pka.

when Pka = -logKa

                  = -log7.2 X 10^-4

                  = 3.14

then we will substitution on H-H equation:

 ∴PH = 3.14 + log (0.623)/(1.41) = 2.99

A. is your answer.  hope this  

Iam pretty sure that the answer is d