solubility rules

chem honors

rule 1

all compounds with group 1 metals and ammonium (NH₄⁺) are soluble

-ates rule

all compounds with nitrates (NO₃^-), chlorates (ClO₃^-), and acetates (C₂H₃O₂^-) are soluble

group 17 rule

all compounds with group 17 elements are soluble EXCEPT silver (I), copper (I), lead (II), and mercury(I) — they are all solids

sulfate rule

all compounds with sulfate (SO₄^-2) are soluble EXCEPT barium sulfate (BaSO₄), lead (II) sulfate (PbSO₄), and strontium sulfate (SrSO₄)

weird rule

all compounds of carbonate (CO₃^-2), phosphate (PO₄^-3), and sulfite (SO₃^-2) are insoluble EXCEPT group 1 metals and ammonium (NH₄⁺)

precipitates (solids)

insoluble compounds that cannot dissolve

oxide / hydroxide rule

all oxides (O^-2) and hydroxides (OH^-) are insoluble EXCEPT group 1 metals, ammonium (NH₄⁺), calcium (Ca⁺²), strontium (Sr⁺²), and barium (Ba⁺²)

sulfide rule

all compounds of sulfide (S^-2) are insoluble EXCEPT group 1 metals, group 2 metals, and ammonium (NH₄⁺)

S

sodium (Na⁺)

N

nitrate (NO₃^-)

A

ammonium (NH₄⁺)

P

potassium (K⁺)

SNAP ions

ALWAYS aqueous and soluble