Sodium sulfide

Chemical compound

Sodium sulfide is a chemical compound with the formula Na2S. More common is its hydrate Na2S·9H2O. Both the anhydrous and the hydrated salts are colorless solids, although technical grades of sodium sulfide are generally yellow to brick red owing to the presence of polysulfides. It is commonly supplied as a crystalline mass, in flake form, or as a fused solid. They are water-soluble, giving strongly alkaline solutions.

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