What is Alcohol

Alcohol is often not thought of as a drug - largely because its use is common for both religious and social purposes in most parts of the world. It is a drug, however, and compulsive drinking in excess has become one of modern society's most serious problems. The beverage alcohol (scientifically known as ethyl alcohol, or ethanol) is produced by fermenting or distilling various fruits, vegetables, or grains. Ethyl alcohol itself is a clear, colorless liquid. Alcoholic beverages get their distinctive colors from the diluents, additives, and by-products of fermentation.

How Alcohol Works :

Alcohol is rapidly absorbed into the bloodstream from the small intestine, and less rapidly from the stomach and colon. In proportion to its concentration in the bloodstream, alcohol decreases activity in parts of the brain and spinal cord. The drinker's blood alcohol concentration depends on:

• the amount consumed in a given time
• the drinker's size, sex, body build, and metabolism
• the type and amount of food in the stomach.

Once the alcohol has passed into the blood, however, no food or beverage can retard or interfere with its effects. Fruit sugar, however, in some cases can shorten the duration of alcohol's effect by speeding up its elimination from the blood.

In the average adult, the rate of metabolism is about 8.5 g of alcohol per hour (i.e. about two-thirds of a regular beer or about 30 mL of spirits an hour). This rate can vary dramatically among individuals, however, depending on such diverse factors as usual amount of drinking, physique, sex, liver size, and genetic factors.

Alcohol is any of a class of organic compounds with the general formula ROH, where R represents an alkyl group made up of carbon and hydrogen in various proportions and OH represents one or more hydroxyl groups . In common usage the term alcohol usually refers to ethanol . The class of alcohols also includes methanol ; the amyl, butyl, and propyl alcohols; the glycols ; and glycerol . An alcohol is generally classified by the number of hydroxyl groups in its molecule. An alcohol that has one hydroxyl group is called monohydric; monohydric alcohols include methanol, ethanol, and isopropanol . Glycols have two hydroxyl groups in their molecules and so are dihydric. Glycerol, with three hydroxyl groups, is trihydric. The monohydric alcohols are further classified as primary, secondary, or tertiary according to the number of carbon atoms bonded to the carbon atom to which the hydroxyl group is bonded. Many of the properties and reactions characteristic of alcohols are due to the electron charge distribution in the COH portion of the molecule (see chemical bond ). Chemical reactions involving the hydroxyl group in an alcohol molecule include: those in which the hydroxyl group is replaced as a whole, e.g., reaction of ethanol with hydrogen iodide to form ethyl iodide and water; those in which only the hydrogen in the hydroxyl group is replaced, e.g., the reaction of ethanol with sodium, an active metal, to form sodium ethoxide and hydrogen; and those in which the carbon-oxygen bond becomes a double bond to form an aldehyde or ketone depending on whether it is a primary or secondary alcohol. Alcohols are generally less volatile, have higher melting points, and are more soluble in water than the corresponding hydrocarbons (in which the OH group is replaced with hydrogen). For example, at room temperature methanol is a liquid, while methane is a gas.