Naphtha polloi]." It enters the word napalm, a contraction of the "na" of "naphthenic acid" and "palm" of "palmitic acid", originally made from a mixture of naphthenic acid combined with aluminium and magnesium salts of palmitic acid. Naphtha is the root of the word naphthalene, and can also be recognised in the word phthalate, and the paint colour phthalo blue. In older usage, "naphtha" simply meant crude oil, but this usage is now obsolete in English. It was also used for mineral spirits (also known as "Stoddard Solvent"), originally the main active ingredient in Fels Naptha laundry soap. The Ukrainian and
Copper naphthenate adhesion promoters, lubricant additives, and catalysts where oil solubility is required. Naphthenic acid is a complex group of carboxylic acids with the general formula CHO where n indicates the carbon number and z specifies the hydrogen deficiency resulting from ring formation. Naphthenic acids occur naturally in crude oil at varying concentrations, and their composition varies with the crude oil composition and the conditions during refining. Crude oils with total acid number (TAN) as little as 0.5 mg KOH/g acid or petroleum fractions greater than about 1.0 mg KOH/g oil usually qualify as a high acid crude or oil. At the