What molar ratio of acetic acid to sodium acetate is required to create a buffer solution at a pH of 4.89 at 25 degree C? Ka for acetic acid is

1.8 X 10-5

A. 2.9
B.0.56
C.1.4
D.0.72
E.0.2 ( I chose this and got is wrong)

I'm lost on how to do these problems, but I started out...

4.89=4.74 + log

got lost after that...

1 answer

pH = pKa + log (base)/(acid)
4.89 = 4.74 + log(b)/(a)
Solve for base/acid ratio. That's the ratio they want.