1. All salts of alkali metal ions (e.g. Group IA elements --> Li, Na, K, Rb, Cs, Fr) are water-soluble.
2. All salts of ammonium (NH4+
) are water-soluble.
- 3. All salts with Cl-, Br-, I- are water soluble
- Except for salts containing Ag+, Pb2+, and Hg22+
- 4. All salts of SO42- (sulfate) ion are water soluble.
- Except for those containing Ca2+, Sr2+, Ba2+, and Pb2+