[peterschmidt3943]

Hello,

Question: which pH do you get when you mix 10mL of 0,1mol of K2HPO4 with 5mL of 0,1mol of HCl?
pK Values of phosphoric acid:
pKa1 = 2,16 pKa2 = 7,2 pKa3 = 12,3

Here, we can use the "Henderson-Hasselbach-equation", but I dont know which pKs to use..

in general, pH=pKs  - lg[[Acid]/[Base]]..
please, I need quick help on this one..

[Borek]

Write the reaction equation. Which acid/conjugate pair dominates the solution?