Basic chemicals represent the foundational, high-volume commodities produced by the chemical industry that serve as raw material inputs for downstream manufacturing processes. This category includes heavy petrochemicals (such as ethylene, propylene, and benzene derived from petroleum refining) as well as bulk inorganic chemicals (such as chlorine, caustic soda, ammonia, and sulfuric acid). They are manufactured in immense quantities to supply agriculture, plastics production, and secondary chemical synthesis.