Salts of Weakly Acidic Cations and Weakly Basic Anions
Both components react with water!
Acidity is determined by the relative acid strength
and base strength of the separated ions.
example: NH4HS
NH4+(aq) + H2O(l) NH3(aq) + H3O+(aq)
HS-(aq) + H2O(l) H2S(aq) + OH-(aq)
Ka(NH4+) = 5.7 x 10-10
Kb(HS-) = 1 x 10-7
Since Kb > Ka, the solution is basic.
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