Element No. 16 is SULFUR, a non-metallic chemical element with the symbol S and atomic number 16. It is abundant, multivalent, and non-metallic. SULFUR is an essential element for life and is found in two amino acids, cysteine and methionine. It is also found in proteins, vitamins, enzymes, and hormones. SULFUR is used in the production of sulfuric acid, fertilizers, and rubber. It is also used in the manufacture of gunpowder, matches, and dyes.