All sodium, potassium, and ammonium salts are soluble. All nitrates, acetates and perchlorates are soluble. All silver, lead and mercury(I) salts are insoluble. All chlorides, bromides and iodides are soluble.

If more solute is added and it does not dissolve, then the original solution was saturated. If the added solute dissolves, then the original solution was unsaturated. A solution that has been allowed to reach equilibrium but which has extra undissolved solute at the bottom of the container must be saturated.

Potassium chloride

Water molecules pull the sodium and chloride ions apart, breaking the ionic bond that held them together. After the salt compounds are pulled apart, the sodium and chloride atoms are surrounded by water molecules, as this diagram shows. Once this happens, the salt is dissolved, resulting in a homogeneous solution.

Sodium chloride is stable. If kept dry, it will remain a free-flowing solid for years. Maximum solubility of NaCl in water at 25 °C is 357 mg/mL. NaCl is unusual in that its solubility does not increase appreciably with temperature, since at 100 °C, the solubility is 384 mg/mL.

Those gases whose molecules are polar are much more soluble in water than are nonpolar gases. Ammonia, a strongly polar molecule, is very soluble in water (89.9 g/100 g H2O); so is hydrogen chloride (82.3 g/100 g H2O)….