Hydrofluoric acid, HF, has a Ka of 6.8E-4. What are [H3O+], [F-], and [OH-] in 0.970 M HF?

I have set up an ICE table and solved for x to be 0.025, and gotten [H3O+]=0.025M. I then used the relations between pH and pOH to find that [OH-]=3.98E-13. However, I thought that [F-] would be 0.025 M too since that is also the change in the ICE table. Apparently it's the wrong answer, so how do I find [F-] in this case?

Question

Hydrofluoric acid, HF, has a Ka of 6.8E-4. What are [H3O+], [F-], and [OH-] in 0.970 M HF?

I have set up an ICE table and solved for x to be 0.025, and gotten [H3O+]=0.025M. I then used the relations between pH and pOH to find that [OH-]=3.98E-13. However, I thought that [F-] would be 0.025 M too since that is also the change in the ICE table. Apparently it's the wrong answer, so how do I find [F-] in this case?

surry99 · Answer

Your answer is correct. At equilm, the [H30+] = [F-] = .02568 M