Solubility chart
Look up the water solubility of common salts, bases and acids — tap a cell to see the compound's formula, name and notes (precipitate colour, unstable compounds…).
| Cation →Anion ↓ | H⁺ | Li⁺ | K⁺ | Na⁺ | NH₄⁺ | Cu²⁺ | Ag⁺ | Mg²⁺ | Ca²⁺ | Ba²⁺ | Zn²⁺ | Hg²⁺ | Al³⁺ | Sn²⁺ | Pb²⁺ | Fe²⁺ | Fe³⁺ |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| OH⁻ | |||||||||||||||||
| Cl⁻ | |||||||||||||||||
| Br⁻ | |||||||||||||||||
| I⁻ | |||||||||||||||||
| NO₃⁻ | |||||||||||||||||
| CH₃COO⁻ | |||||||||||||||||
| S²⁻ | |||||||||||||||||
| SO₃²⁻ | |||||||||||||||||
| SO₄²⁻ | |||||||||||||||||
| CO₃²⁻ | |||||||||||||||||
| SiO₃²⁻ | |||||||||||||||||
| PO₄³⁻ |
T SolubleI Slightly solubleK Insoluble– Does not exist or decomposes in waterB: volatile acid, or decomposes into a gas · KB: non-volatile acid
How to read the chart
Each cell is the intersection of a cation (column) and an anion (row), showing whether the ionic compound is soluble (T), slightly soluble (I) or insoluble (K) in water at room temperature. A “–” means the compound does not exist or decomposes in water. The H⁺ column describes the corresponding acid of each anion: B means volatile (or decomposes into a gas), KB means non-volatile.
Quick rules of thumb
- All nitrates (NO₃⁻) and acetates (CH₃COO⁻) are soluble.
- Salts of alkali metals (Na⁺, K⁺, Li⁺) and ammonium (NH₄⁺) are almost all soluble.
- Most chlorides are soluble, except AgCl (insoluble) and PbCl₂ (slightly soluble).
- Most sulfates are soluble, except BaSO₄ and PbSO₄ (insoluble); CaSO₄ and Ag₂SO₄ are slightly soluble.
- Most carbonates, sulfites, phosphates and silicates are insoluble, except those of alkali metals and ammonium.
- Soluble bases (alkalis): NaOH, KOH, Ba(OH)₂, LiOH; Ca(OH)₂ is slightly soluble — most other hydroxides are insoluble.