Compound Solubility Guidelines

Compound Solubility Guidelines

General Principles

• Solubility Rule: Soluble compounds dissociate into ions in a solution, while insoluble compounds remain intact.

Soluble Compounds

• Group 1 Metals

  • All salts containing Group 1 metals (e.g., Li+, Na+, K+) are soluble.
  • No exceptions.

• Ammonium (NH4+)

  • All ammonium salts are soluble.
  • No exceptions.

• Nitrates (NO3-) and Acetates (CH3COO-)

  • All salts containing nitrates and acetates are soluble.
  • No exceptions.

• Perchlorates (ClO4-)

  • All perchlorate salts are soluble.
  • No exceptions.

• Halides (Cl-, Br-, I-)

  • All halide salts are soluble except for those containing Ag+, Pb2+, and Hg2²+.

• Sulfates (SO4²-)

  • All sulfate salts are soluble except for those containing Ba2+, Sr2+, Pb2+, and Ca2+.

Insoluble Compounds

• Carbonates (CO3²-) and Phosphates (PO4³-)

  • Generally insoluble except when combined with Group 1 cations or NH4+.

• Sulfides (S²-)

  • Generally insoluble.

• Hydroxides (OH-)

  • Generally insoluble; however, they are soluble when associated with Group 1 and Group 2 cations or NH4+.

• Chromates (CrO4²-) and Oxalates (C2O4²-)

  • - Soluble with Group 1 cations or Ba2+, and soluble with Group 1 cations or NH4+.
  • Slightly soluble with Ca2+ or Sr2+, and generally insoluble otherwise.

Summary of Exceptions

• Insoluble Exceptions:
  • Sulfates: Insoluble with Ba2+, Sr2+, Pb2+, Ca2+.
  • Halides: Insoluble with Ag+, Pb2+, Hg2²+.
  • For carbonates and phosphates: insoluble unless with Group 1 or NH4+.
  • General insolubility for sulfides, with hydroxides, chromates, and oxalates having specific solubility conditions.