1. The problem statement, all variables and given/known data What concentration of formic acid would give an aqueous solution in which 2.85 percent of the formic acid molecules are ionized? Assume that Ka for formic acid is 1.80E-4 . 2. Relevant equations 3. The attempt at a solution X^2 / .0285 - X = 1.8E-4 X = .00226 M = .0285 - .00226 = .0262M This is wrong. Any ideas?