...............HA ==> H^+ + A^-
begin.........0.04M....0......0
change..........-x......+x.....+x
final.......0.04-x......x.......x
Ka = (H^+)(A^-)/(HA)
You know pH, convert to (H^+) and that will be x. Substitute into Ka expression and solve for Ka.
A 0.040M solution of a weak acid has a pH of 3.02 at 25°C . What is the value of Ka for the acid?
1 answer