Aqueous Salt Solutions - Acid and Base Properties

Salts contain ions that may affect the pH in aqueous solutions in both acidic and basic directions. This tool helps predict whether an aqueous solution of a salt will be basic, acidic, or neutral by comparing the Ka value for the acidic ion with the Kb value for the basic ion.

Type of SaltExamplespH of SolutionComment
Strong base + Strong acidBaCl2, KCl, CaNO3, Na2SO47Neutral - Neither acts as an acid or a base
Strong base + Weak acidNaF, KCHOO, NaHCO3> 7Basic - Anion acts as a base, Cation has no effect on pH
Conjugate acid of weak base + Strong acidNH4Br, NH4NO3< 7Acidic - Cation acts as an acid, Anion has no effect on pH
Conjugate acid of weak base + Conjugate base of weak acidNH4CN, NH4CH3COODepends on Ka vs KbAcidic if Ka > Kb, Basic if Kb > Ka, Neutral if Ka = Kb
Highly charged metal ion + Strong acidAl(NO3)3, CrCl3< 7Acidic - Hydrated cations acts as an acid, Anion has no effect on pH
Ka vs KbpHBasic or Acidic
Ka > Kb< 7Acidic
Ka < Kb> 7Basic
Ka = Kb7Neutral