[vertsky]

Hello everyone,
I have this chemistry problem that doesn't make any sense to me.
here it is: At equilibrium, a certain acid, HA, in solution, has a concentration of 0.94 M and its conjugate base has a concentration of 0.060 M. calculate Ka.

First of all, I know that to find Ka I use its definition, which would be Ka=[H+]*[A-]/[HA], but for this problem, all I know is the [A-], which would be .06, and the [HA], which would be .94.

I have a feeling that the fact that the HA and A- add up to 1 might have something to do with getting the answer, but I could be completely mistaken on that point.

Please let me know how I can figure this out, I would really appreciate any help at all.

Thanks!! 

[Borek]

What do you miss to calculate Ka? Write dissociation reaction and think what you can get from the stoichiometry.