The ionization equation of nitrite ion will be
                          Â
NO2- + H2O --> HNO2 + OH-
Initial                  Â
0.1Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
0Â Â Â Â Â Â Â Â Â Â Â Â Â
0
Change             Â
-x                        Â
x               Â
x
Equilibrium      Â
0.1-x                   Â
x               Â
x
x = 0.0015 X 0.1 / 100 = 0.00000015
Kb = [HNO2] [ OH-] / [NO2-]
Kb = 0.00000015 X 0.00000015 / 0.1 -0.00000015 =
Kb = 2.25 X 10^-11
