Ethanol is manufactured by direct hydration of ethene or by fermentation if petroleum sources are scarce, as in Brazil.
Wine goes off by a similar process, turning vinegary.
Ethanol can react with carboxylic acids in an esterification reaction, often catalysed by concentrated sulphuric acid. Sulphuric acid and ethanol react in a variety of ways, depending on their relative amounts and the temperature, giving ethyl hydrogen sulphate, ethoxyethane and ethene for example. Ethanol's most common use is in alcoholic drinks. Physiologically it acts as a depressant, despite its apparent stimulant effect caused by removal of inhibitions. Another major use is as a solvent, the second most important after water.