......HA ==> H^+ + A^-
I.....0.5....0......0
C.....-x.....x......x
E...0.5-x....x......x
Enter the E line into Ka expression and solve for Ka. The problem tells you the pH which will give you the (H^+) and (A^-). Then convert to pKa.
You need to determine the pKa of a weak, monoprotic acid. You add 0.500 moles of the acid to 1.00 L of water. The resulting pH was 1.87. What is the pKa of this weak acid? You may ignore the autoionization of water.
2.74
3.43
5.38
2.01
1.87
1 answer