[liravsc]

"Find the pKa for an HA acid. The HA and A^- concentrations are, respectively, 0.075 and 0.025. The pH is 6."

I used Henderson-Hasselbach's equation and got 6.477. Just want to check if that was correct. Studying for an exam after arriving 1 month late to class 

Thank you.

[Borek]

Logic (and the value) is OK, you can get punished for significant digits though.