Reactions :  Solubility Rules

Soluble - A salt is considered soluble if it dissolves in water to give a solution with a concentration of at least 0.1 M at room temperature.

Insoluble - A salt is considered insoluble if the concentration of an aqueous solution is les than 0.0001 M at room temperature.

Salts with solubilities between 0.0001 M and 0.1 M are considered to be slightly soluble.

Soluble: Dissolve - Do NOT form a solid precipitate.

  1. **alkali metal ions and ammonium ion: Li+, Na+, K+, NH4+
  2. acetate ion: C2H3O21-
  3. nitrate ion: NO31-
  4. halide ions (X): Cl-, Br-, I-  (Exceptions:  AgX, HgX, and PbX2 are insoluble)
  5. sulfate ion: SO42-  (Exceptions:  SrSO4, BaSO4, and PbSO4 are insoluble;
                         AgSO4, CaSO4, and Hg2SO4 are slightly soluble)

Insoluble: Do NOT Dissolve - Do form a solid precipitate.

  1. carbonate ion: CO32-
  2. chromate ion: CrO42-
  3. phosphate ion: PO43-
  4. sulfide ion: S2-  (Exceptions:  CaS, SrS, and BaS are soluble)
  5. hydroxide ion: OH-  (Exceptions:  Sr(OH)2 and Ba(OH)2 are soluble;
                         Ca(OH)2 is slightly soluble)

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