is the ka value of HNO2 my equation NO2 + H2O - - > HNO2 + OH^- therefore i need the Kb of NO2 so i do: Kw/Ka 1.0E-14/5.6E-4 = ans 1 square root of (ans1 * 0.22) = 1.98208...E-6 check if within 5% and find it is well below 5% so valid. ...