What is the pH of a 0.20 M solution of NH4Cl? [Kb(NH3) = 1.8 × 10−5]

Answer 1

NH4^+ + H2O ==> H3O^+ + NH3

Set up an ICE chart, then substitute into the following:
Ka = (Kw/Kb) = (H3O^+)(NH3)/(NH4^+)
(H3O^+) = x = (NH3)
(NH4^+) = (0.2-x)

Answer 2

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