Use the Henderson-Hasselbalch equation. I don't know the value you are using for pk2 so I can't work the problem for you.
6.9 = pK2 + log base/acid
Solve for base/acid = ? That's equation 1.
Equation 2 is
base + acid = 0.2M
Solve those two equations simultaneously for base and acid concentrations
You want 1 L so convert M base and acid to mols.
...HPO4^2- + H^+ ==> H2PO4^- + H2O
I
C
E
Complete the ICE chart.
If you have any trouble repost but show your work and where you get stuck.
How would you prepare 1.000 L of a 0.200 M phosphate buffer at pH 6.90 using crystalline Na2HPO4 and a solution of 1.000 M HCl?
1 answer