Chapter 16 - Sulfur, Selenium, and Tellurium

Abstract

Sulfur, S8, is found uncombined below the earth’s surface and in many minerals. Selenium and tellurium are usually found with sulfur compounds. Chemically, Se and Te are more metallic in character than is sulfur, but they form oxides and halides in reactions with oxygen and halogens. Although SF6 is almost inert, SF4 is a reactive fluorinating agent. Except for SF6, the halogens of S, Se, and Te undergo hydrolysis reactions. Sulfur, selenium, and tellurium form binary compounds in reactions with metals. Compounds with hydrogen include H2X, but sulfur also forms some sulfanes, H2Sn, that contain chains of sulfur atoms with hydrogen atoms in terminal positions. The oxides of the elements are acidic with the most important being SO3, the anhydride of sulfuric acid, the chemical that is produced in largest quantity. The major use of H2SO4 is in the production of fertilizers, but there are many other important uses.