Dimethyl sulfoxide (DMSO) is a sulfur-containing organic compound with the molecular formula C₂H₆OS. At room temperature, it appears as a colorless, odorless transparent liquid and is a hygroscopic flammable liquid. It exhibits high polarity, a high boiling point, good thermal stability, is aprotic, and is miscible with water. It can dissolve in most organic substances such as ethanol, propanol, benzene, and chloroform, earning it the reputation of a "universal solvent." When heated in the presence of acid, it produces small amounts of compounds such as methyl mercaptan, formaldehyde, dimethyl sulfide, and methanesulfonic acid. It decomposes at high temperatures and reacts violently with chlorine. When burned in air, it emits a pale blue flame. It can be used as an organic solvent, reaction medium, and intermediate in organic synthesis. It also serves as a dye solvent, decolorizing agent, dye carrier in synthetic fiber production, as well as an absorbent for recovering acetylene and sulfur dioxide.