Sulfur is an essential element for all life, but almost always in the form of organo sulfur compounds or metal sulfides.

Sulfur is the tenth most abundant element by mass in the universe and the fifth most on Earth.

Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula S8.

Sulfur is an essential element for all life, but almost always in the form of organo sulfur compounds or metal sulfides.

Treatment of sulfur with hydrogen gives hydrogen sulfide. When dissolved in water, hydrogen sulfide is mildly acidic:

Sulfur reacts directly with methane to give carbon disulfide, which is used to manufacture cellophane and rayon.

Sulfur is increasingly used as a component of fertilizers. The most important form of sulfur for fertilizer is the mineral calcium sulfate. Elemental sulfur is hydrophobic (not soluble in water) and cannot be used directly by plants. Over time, soil bacteria can convert it to soluble derivatives, which can then be used by plants. Sulfur improves the efficiency of other essential plant nutrients, particularly nitrogen and phosphorus.