Solubility Rules

Use Solubility Rules to identify if the compound is soluble in water (aqueous solution)

NaCl - Sodium chloride

Group 1 ions (always soluble)

KCl - Potassium chloride

Group 1 ions (always soluble)

LiCl - Lithium chloride

Group 1 ions (always soluble)

NaBr - Sodium bromide

Group 1 ions (always soluble)

KBr - Potassium bromide

Group 1 ions (always soluble)

LiBr - Lithium bromide

Group 1 ions (always soluble)

NaI - Sodium iodide

Group 1 ions (always soluble)

KI - Potassium iodide

Group 1 ions (always soluble)

LiI - Lithium iodide

Group 1 ions (always soluble)

NH₄Cl - Ammonium chloride

Ammonium compounds are soluble

NH₄Br - Ammonium bromide

Ammonium compounds are soluble

NH₄I - Ammonium iodide

Ammonium compounds are soluble

NaNO₃ - Sodium nitrate

Nitrates always soluble

KNO₃ - Potassium nitrate

Nitrates always soluble

LiNO₃ - Lithium nitrate

Nitrates always soluble

NH₄NO₃ - Ammonium nitrate

Nitrates + ammonium

NaC₂H₃O₂ - Sodium acetate

Acetates always soluble

KC₂H₃O₂ - Potassium acetate

Acetates always soluble

LiC₂H₃O₂ - Lithium acetate

Acetates always soluble

NH₄C₂H₃O₂ - Ammonium acetate

Acetates + ammonium

Na₂SO₄ - Sodium sulfate

Group 1; sulfates soluble except PMS/Castrobear

K₂SO₄ - Potassium sulfate

Group 1 ions (always soluble)

Li₂SO₄ - Lithium sulfate

Group 1 ions (always soluble)

(NH₄)₂SO₄ - Ammonium sulfate

Ammonium compounds are soluble

Na₂CO₃ - Sodium carbonate

Group 1 ions (always soluble)

K₂CO₃ - Potassium carbonate

Group 1 ions (always soluble)

Li₂CO₃ - Lithium carbonate

Group 1 ions (always soluble)

NaHCO₃ - Sodium bicarbonate

Group 1 ions (always soluble)

KHCO₃ - Potassium bicarbonate

Group 1 ions (always soluble)

NH₄HCO₃ - Ammonium bicarbonate

Ammonium compounds are soluble

NaOH - Sodium hydroxide

Group 1 ions (always soluble)

KOH - Potassium hydroxide

Group 1 ions (always soluble)

LiOH - Lithium hydroxide

Group 1 ions (always soluble)

NaClO₃ - Sodium chlorate

Chlorates always soluble

KClO₃ - Potassium chlorate

Chlorates always soluble

NaClO₄ - Sodium perchlorate

Perchlorates soluble

KClO₄ - Potassium perchlorate

Perchlorates soluble

Na₂CrO₄ - Sodium chromate

Group 1 ions (always soluble)

K₂CrO₄ - Potassium chromate

Group 1 ions (always soluble)

Na₂S - Sodium sulfide

Group 1 ions (always soluble)

K₂S - Potassium sulfide

Group 1 ions (always soluble)

(NH₄)₂S - Ammonium sulfide

Ammonium compounds are soluble

Na₃PO₄ - Sodium phosphate

Group 1 ions (always soluble)

K₃PO₄ - Potassium phosphate

Group 1 ions (always soluble)

NaF - Sodium fluoride

Group 1 (halides soluble except PMS)

KF - Potassium fluoride

Group 1 ions (always soluble)

NH₄F - Ammonium fluoride

Ammonium compounds are soluble

Na₂SO₃ - Sodium sulfite

Group 1 ions (always soluble)

K₂SO₃ - Potassium sulfite

Group 1 ions (always soluble)

(NH₄)₂SO₃ - Ammonium sulfite

Ammonium compounds are soluble

AgCl - Silver(I) chloride

PMS exception

AgBr - Silver(I) bromide

PMS exception

AgI - Silver(I) iodide

PMS exception

PbCl₂ - Lead(II) chloride

PMS exception

PbBr₂ - Lead(II) bromide

PMS exception

PbI₂ - Lead(II) iodide

PMS exception

Hg₂Cl₂ - Mercury(I) chloride

PMS exception

Hg₂Br₂ - Mercury(I) bromide

PMS exception

Hg₂I₂ - Mercury(I) iodide

PMS exception

CaSO₄ - Calcium sulfate

Castrobear exception

SrSO₄ - Strontium sulfate

PMS & Castrobear

BaSO₄ - Barium sulfate

Castrobear exception

PbSO₄ - Lead(II) sulfate

PMS exception

Ag₂SO₄ - Silver sulfate

PMS exception

CaCO₃ - Calcium carbonate

Carbonates insoluble (except Group 1 & NH₄⁺)

SrCO₃ - Strontium carbonate

Carbonates insoluble (except Group 1 & NH₄⁺)

BaCO₃ - Barium carbonate

Carbonates insoluble (except Group 1 & NH₄⁺)

PbCO₃ - Lead(II) carbonate

Carbonates insoluble (except Group 1 & NH₄⁺)

Ag₂CO₃ - Silver carbonate

Carbonates insoluble (except Group 1 & NH₄⁺)

Ca₃(PO₄)₂ - Calcium phosphate

Phosphates insoluble (except Group 1/NH₄⁺)

Sr₃(PO₄)₂ - Strontium phosphate

Phosphates insoluble (except Group 1/NH₄⁺)

Ba₃(PO₄)₂ - Barium phosphate

Phosphates insoluble (except Group 1/NH₄⁺)

Pb₃(PO₄)₂ - Lead phosphate

Phosphates insoluble (except Group 1/NH₄⁺)

Ag₃PO₄ - Silver phosphate

Phosphates insoluble (except Group 1/NH₄⁺)

Fe(OH)₃ - Iron(III) hydroxide

Hydroxides insoluble (except Group 1)

Fe(OH)₂ - Iron(II) hydroxide

Hydroxides insoluble (except Group 1)

Al(OH)₃ - Aluminum hydroxide

Hydroxides insoluble (except Group 1)

Cu(OH)₂ - Copper(II) hydroxide

Hydroxides insoluble (except Group 1)

Mg(OH)₂ - Magnesium hydroxide

Hydroxides insoluble (except Group 1)

Ca(OH)₂ - Calcium hydroxide

Slightly soluble → treated as insoluble

FeS - Iron(II) sulfide

Sulfides insoluble except Group 1/NH₄⁺

CuS - Copper(II) sulfide

Sulfides insoluble except Group 1/NH₄⁺

PbS - Lead(II) sulfide

Sulfides insoluble except Group 1/NH₄⁺

Ag₂S - Silver sulfide

Sulfides insoluble except Group 1/NH₄⁺

HgS - Mercury(II) sulfide

Sulfides insoluble except Group 1/NH₄⁺

ZnS - Zinc sulfide

Sulfides insoluble except Group 1/NH₄⁺

Al₂S₃ - Aluminum sulfide

Sulfides insoluble except Group 1/NH₄⁺

Mg₃(PO₄)₂ - Magnesium phosphate

Phosphates insoluble (except Group 1/NH₄⁺)

FePO₄ - Iron(III) phosphate

Phosphates insoluble (except Group 1/NH₄⁺)

Cu₃(PO₄)₂ - Copper(II) phosphate

Phosphates insoluble (except Group 1/NH₄⁺)

Cr(OH)₃ - Chromium(III) hydroxide

Hydroxides insoluble (except Group 1)

Mn(OH)₂ - Manganese(II) hydroxide

Hydroxides insoluble (except Group 1)

Co(OH)₂ - Cobalt(II) hydroxide

Hydroxides insoluble (except Group 1)

Ni(OH)₂ - Nickel(II) hydroxide

Hydroxides insoluble (except Group 1)

Sn(OH)₂ - Tin(II) hydroxide

Hydroxides insoluble (except Group 1)

SnS - Tin(II) sulfide

Sulfides insoluble except Group 1/NH₄⁺

CoS - Cobalt(II) sulfide

Sulfides insoluble except Group 1/NH₄⁺

NiS - Nickel(II) sulfide

Sulfides insoluble except Group 1/NH₄⁺