Known to the ancients (in Genesis it is called brimstone), sulfur was first classified as an element in 1777 by Antoine Lavoisier. It is estimated to be the ninth most abundant element in the universe. In the form of sulfides, sulfates, and elemental sulfur, the element constitutes about 0.03 percent of the Earth's crust. After oxygen and silicon, it is the most abundant constituent of minerals. Occurrence, properties, and uses. Native or free sulfur occurs chiefly in …showed first 75 words of 1269 total…

…showed last 75 words of 1269 total…amino acids (e.g., cysteine, methionine, and taurine), which are key components of hormones, enzymes, and coenzymes. Significant, too, are the synthetic organic sulfur compounds, among them numerous pharmaceuticals (sulfa drugs, dermatological agents), insecticides, solvents, and agents such as those used in preparing rubber and rayon. Atomic number: 16 Atomic weight: 32.064 Melting point: Rhombic 112.8° C (235° F) Monoclinic 119° C (246° F) Boiling point: 444.6° C (832° F) Density @ 20° C [68° F] Rhombic 2.07 g/cm3 Monoclinic 1.96 g/cm3 Oxidation states: -2, +4, and +6