Potassium sulfide

Potassium sulfide is a chemical compound. Its chemical formula is K2S. It contains potassium and sulfide ions. The potassium is in its +1 oxidation state.
Properties.
Potassium sulfide is a colorless solid when it is pure. Sometimes it is not pure and it is yellow-brown. It reacts with water to make KHS, potassium hydrogen sulfide, and potassium hydroxide. It reacts with acids to make hydrogen sulfide and a potassium salt. 
Preparation.
Potassium sulfide is made by reacting potassium with sulfur. Many times the potassium is dissolved in liquid ammonia. It can also be made by reacting potassium sulfate with carbon. It is made when black powder is burned.