Sodium sulfide is a chemical compound with the formula Na2S. It appears as a yellow to white solid and is highly soluble in water. This compound is primarily used in various industrial applications, including the production of sodium thiosulfate, paper manufacturing, and in the tanning of leather. In addition to its industrial uses, sodium sulfide is also employed in laboratories for chemical synthesis and as a reducing agent. It can release hydrogen sulfide gas when it reacts with acids, which is important to consider for safety and handling.