Potassium sulfide is an insoluble compound, it is not soluble in water. It dissolves in acetone and glycerol, but not in ether. It is produced by reacting potassium carbonate with sulfuric acid and is used as a fertilizer. It is also used as a dyeing agent and in some photographic processes.

It is a flammable substance that may ignite spontaneously when in contact with air or some metals. It is also unstable and may explode on percussion or rapid heating. Its vapors are irritant and may cause irritation to the eyes, nose, throat and lungs. It is very toxic when inhaled and ingested.

It has the chemical formula K2SO4. The 2 in the equation refers to the number of potassium ions present in the compound. The sulfate ions have a negative charge. As such, they have a tendency to pair with positive ions such as the chloride ions present in water. This is what makes sulfate salts more soluble than chloride salts.

Ionic compounds are easily dissolved in water, but covalent compounds are not. Sulfate salts dissociate in water to form hydrogen and sulfate ions. This is because sulfate ions have fewer hydration electrons than chloride ions.