Period 3 element phosphorus originates from oxidation of the white (but not red) phosphorus and should be called chemiluminescence. It is also the lightest element to easily produce stable exceptions to the octet rule. The vast majority of phosphorus compounds are consumed as fertilizers. Other applications include the role of organophosphorus compounds in detergents, pesticides and nerve agents, and matches. "Sulfur" (symbol S) is an abundant, multivalentnon-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S. Elemental sulfur is a bright yellow crystalline solid when at room temperature. Chemically, sulfur can react as either an oxidant or reducing agent.
Black and white Black and white Black-and-white (B/W or B&W) images combine black and white in a continuous spectrum, producing a range of shades of gray. The history of various visual media has typically begun with black and white, and as technology improved, altered to color. However, there are exceptions to this rule, including black-and-white fine art photography and in motion pictures, many art films. Most early forms of motion pictures or film were black and white. Some color film processes, including hand coloring were experimented with, and in limited use, from the earliest days of motion pictures. The switch from most films