"Alcohol" - what is it, definition of the term
Ethanol, a volatile, colorless, flammable liquid with the molecular formula C₂H₅OH, belongs to the class of hydroxylated hydrocarbons; it functions as a central‑nervous‑system depressant, is produced naturally through the fermentation of sugars by microorganisms, and can also be manufactured synthetically for use as a solvent, fuel, and antiseptic.
Detailed information
Ethanol (C₂H₅OH) is a colorless, volatile liquid produced by fermentation of sugars or by catalytic hydration of ethylene. Its molecular structure contains a hydroxyl group attached to a two‑carbon chain, granting both polar and non‑polar characteristics.
Industrial production relies on two primary pathways. Fermentation converts carbohydrates from grains, fruits, or molasses into ethanol and carbon dioxide using yeast. Synthetic routes hydrate ethylene derived from petroleum, yielding high‑purity ethanol suitable for technical applications.
Key applications include:
- Consumption as a beverage component, regulated by concentration and labeling standards.
- Solvent for pharmaceuticals, cosmetics, and printing inks because of its ability to dissolve a wide range of organic compounds.
- Antiseptic in medical settings, effective against a broad spectrum of microorganisms.
- Additive in gasoline, enhancing octane rating and reducing emissions.
Acute exposure leads to central nervous system depression, impaired coordination, and respiratory depression at high concentrations. Chronic intake correlates with liver cirrhosis, cardiovascular disease, and increased cancer risk. Metabolism occurs primarily in the liver via alcohol dehydrogenase, converting ethanol to acetaldehyde and then to acetate, which enters the citric acid cycle.
Legal frameworks classify ethanol-containing products by intended use and alcohol by volume. Beverage categories are subject to age restrictions, taxation, and labeling requirements. Industrial and fuel grades are exempt from consumption regulations but must meet purity and safety specifications.
In entomological practice, ethanol serves as a preservative for specimens such as ticks, lice, fleas, and other arthropods. Immersion in a 70–95 % ethanol solution prevents decomposition, maintains morphological integrity, and facilitates later microscopic examination. Additionally, ethanol‑based solutions act as carriers for attractants in trap designs targeting biting insects, improving capture efficiency without introducing toxic residues.