AP CHEM Solubility Rules and Exceptions + Polyatomic ion

All soluable in water

Group 1 ions

Li, Na, K, Rb, Cs, Fr

All have a plus one charge

Ammonium( NH4 -)

Nitrate( NO3 -)

Acetate( C2H3O2 -) OR ( CH3COO-)

Chlorate( ClO3-)

Ions with exceptions (of those that form soluble compounds)

Halides:

• Cl-

• Br-

• I-

Exceptions: Insoluble when

• when combined with Ag+ (silver)

• Pb 2+ (lead)

• Hg2 2+ (mercury)

Sulfates:

• SO4 2-

Exceptions: insoluble when

• when combined with Ag+ (silver)

• Ca 2+ (calcium)

• Sr 2+ (strontium)

• Ba 2+ (barium)

• Pb 2+ (lead)

Ions that are Insoluble in water and their exceptions

• Carbonate ( CO3 2-)

  → when combined with group 1 ions or ammonium

• Chromate (CrO4 2-)

  → When combined with group 1 ions, ammonium (NH4), Ca 2+, or Mg 2+

• Phosphate (PO4 3-)

  → When combined with group 1 ions or ammonium (NH4)

• Sulfide( S 2-)

  → When combined with Group 1 ions or ammonium(NH4)

• Hydroxide (OH-)

  → When combined with group 1 ions, ammonium (NH4), Ca 2+, Ba 2+, and Sr 2+

Polyatomic ions

Study as well