pH + pOH = 14
pOH = 14 -9.95
pOH = 4.05
[OH-] = 10^-4.05
[OH-] = 8.9 x 10^-5 M
x = [OH-] = 8.9 x 10^-5 M
B + H2O ----------------------> BH+Â Â Â +
OH-
0.10Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 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 0Â Â
------------------> initial
-x                                          Â
+ x        +x
-----------------> changed
0.10-x                                      Â
x          x
----------------------> equilibrium
Kb = [BH+][OH-]/[B]
Kb = x^2 / 0.1-x
Kb = (8.9 x 10^-5)^2 / (0.1-8.9 x 10^-5)
Kb = 7.93 x 10^-8
