The chemical representation for naphthenic acid is given by ___________________?
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Answer: B. CnH2n-2O2
Explanation
Naphthenic acids are naturally occurring carboxylic acids possessing cyclic alkane structures and specific formulas. The general chemical formula CnH2n-2O2 accurately reflects their monocarboxylic acid and cycloaliphatic ring nature. These organic acids are extracted directly from various heavy crude oil distillate fractions during refining. Carboxylic acids feature a polar carboxyl functional group attached to a hydrocarbon backbone structure. Cycloaliphatic rings contain closed rings of carbon atoms bonded exclusively with single covalent bonds. The variable letter n represents the total number of carbon atoms present in the organic molecule.
Naphthenic acids cause severe corrosion in high-temperature refinery distillation units and piping networks. Refiners use neutralization and caustic washing techniques to remove acidic compounds from petroleum streams. Recovered naphthenic acids find commercial applications as metal soaps, wood preservatives, and drying agents. The formula CnH2n+2O2 describes saturated straight-chain aliphatic diols or different oxygenated organic compounds. Saturated monocarboxylic fatty acids follow the general formula CnH2nO2 without any cyclic ring structures. Complex empirical formulas with arbitrary carbon restrictions do not represent standard naphthenic acid chemistry.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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