Reference library

Solubility Rules

A quick guide to predicting solubility of ionic compounds in water at room temperature.

Usually soluble

Group 1 and ammonium salts are soluble. Nitrates and acetates are generally soluble. Chlorides, bromides and iodides are usually soluble except certain Ag⁺, Pb²⁺ and Hg₂²⁺ salts.

Often insoluble

Carbonates, phosphates and most hydroxides are generally insoluble except with group 1 or ammonium ions. Sulfates are often soluble, but BaSO₄ and PbSO₄ are poorly soluble. Always consult measured data for borderline cases.