Author: Charles Frank

Ethanol Definition, Formula, Uses, & Facts

alcohol in science

The boiling point of the alcohol ethanol is 78.29 °C, compared to 69 °C for the hydrocarbon hexane, and 34.6 °C for diethyl ether. Those groups can form hydrogen bonds to one another and to most other compounds. Owing to the presence of the polar OH alcohols are more water-soluble than simple hydrocarbons. This article covers the structure and classification, physical properties, commercial importance, sources, and reactions of alcohols. For more information about closely related compounds, see chemical compound, phenol, and ether. Globally, the WHO European Region has the highest alcohol consumption level and the highest proportion of drinkers in the population.

Dehydration of the constant-boiling-point mixture yields anhydrous, or absolute, alcohol. Ethanol intended for industrial use is usually denatured (rendered unfit to drink), typically with methanol, benzene, or kerosene. Alcohol, any of a class of organic compounds characterized by one or more hydroxyl (―OH) groups attached to a carbon atom of an alkyl group (hydrocarbon chain). Alcohols may be considered as organic derivatives of water (H2O) in which one of the hydrogen atoms has been replaced by an alkyl group, typically represented by R in organic structures. For example, in ethanol (or ethyl alcohol) the alkyl group is the ethyl group, ―CH2CH3.

  1. Alcohols are classified according to the number of carbon atoms attached to the carbon atom that is attached to the OH group.
  2. In this article, we will examine all of the ways in which alcohol affects the human body.
  3. Ethanol-water mixtures have less volume than the sum of their individual components at the given fractions.
  4. Alcohols may be classified as primary, secondary, or tertiary, according to which carbon of the alkyl group is bonded to the hydroxyl group.

The brain impulses that initiate muscle movement originate in the motor centers of the cerebral cortex and travel through the medulla and spinal cord to the muscles. As the nerve signals pass through the medulla, they are influenced by nerve impulses from the cerebellum. For example, you can normally touch your finger to your nose in one smooth motion with your eyes closed; if your cerebellum were not functioning, the motion would be extremely shaky or jerky. As alcohol affects the cerebellum, muscle movements become uncoordinated. Nerve cells talk to each other and to other cells (such as muscle or gland cells) by sending chemical messages.

It all depends on the amount of alcohol consumed, a person’s history with alcohol and a person’s personality. Ethylene produced from sugar-derived ethanol (primarily in Brazil) competes with ethylene produced from petrochemical feedstocks such as naphtha and ethane. In archaic nomenclature, alcohols can be named as derivatives of methanol using “-carbinol” as the ending. Despite this, the question of beneficial effects of alcohol has been a contentious issue in research for years.

How the Body Responds to Alcohol

This inexpensive and indirect method has a long history in the beer brewing industry. The addition of even a few percent of ethanol to water sharply reduces the surface tension of water. When wine is swirled in a glass, ethanol evaporates quickly from the thin film of wine on the wall of the glass. As the wine’s ethanol content decreases, its surface tension increases and the thin film “beads up” and runs down the glass in channels rather than as a smooth sheet.

alcohol in science

The medulla, or brain stem, controls or influences all of the bodily functions that are involuntary, like breathing, heart rate, temperature and consciousness. As alcohol starts to influence upper centers in the medulla, such as the reticular formation, a person will start to feel sleepy and may eventually become unconscious as BAC increases. If the BAC gets high enough to influence the breathing, heart rate and temperature centers, a person will breathe slowly or stop breathing altogether, and both blood pressure and body temperature will fall. If you have seen someone who has had too much to drink, you’ve probably noticed how drinking alcohol causes definite changes in that person’s performance and behavior. The body responds to alcohol in stages, which correspond to an increase in blood alcohol concentration. Because of hydrogen bonding, alcohols tend to have higher boiling points than comparable hydrocarbons and ethers.

Ethanol is considered a universal solvent, as its molecular structure allows for the dissolving of both polar, hydrophilic and nonpolar, hydrophobic compounds. As ethanol also has a low boiling point, it is easy to remove from a solution that has been used to dissolve other compounds, making it a popular extracting agent for botanical oils. Cannabis oil extraction methods often use ethanol as an extraction solvent,[71] and also as a post-processing solvent to remove oils, waxes, and chlorophyll from solution in a process known as winterization. Pure ethanol is a colourless flammable liquid (boiling point 78.5 °C [173.3 °F]) with an agreeable ethereal odour and a burning taste. Moderate amounts relax the muscles and produce an apparent stimulating effect by depressing the inhibitory activities of the brain, but larger amounts impair coordination and judgment, finally producing coma and death.

Ziegler and oxo processes

Grignard reagents react with carbonyl groups to secondary and tertiary alcohols. Related reactions are the Barbier reaction and the Nozaki-Hiyama reaction. It doesn’t matter how much you drink – the risk to the drinker’s health starts from the first drop of any alcoholic beverage. Finally, alcohol abuse and dependence cause emotional and social problems.

Reagents useful for the transformation of primary alcohols to aldehydes are normally also suitable for the oxidation of secondary alcohols to ketones. The direct oxidation of primary alcohols to carboxylic acids can be carried out using potassium permanganate or the Jones reagent. The direct oxidation of primary alcohols to carboxylic acids normally proceeds via the corresponding aldehyde, which is transformed via an aldehyde hydrate (R−CH(OH)2) by reaction with water before it can be further oxidized to the carboxylic acid. Many alcohols are produced by hydroxylation, i.e., the installation of a hydroxy group using oxygen or a related oxidant.

alcohol in science

Fermentation is the process of culturing yeast under favorable thermal conditions to produce alcohol. Toxicity of ethanol to yeast limits the ethanol concentration obtainable by brewing; higher concentrations, therefore, are obtained by fortification or distillation. The most ethanol-tolerant yeast strains can survive up to approximately 18% ethanol by volume. Ethanol is produced both as a petrochemical, through the hydration of ethylene and, via biological processes, by fermenting sugars with yeast.[96] Which process is more economical depends on prevailing prices of petroleum and grain feed stocks. Upon treatment with strong acids, alcohols undergo the E1 elimination reaction to produce alkenes. The reaction, in general, obeys Zaitsev’s Rule, which states that the most stable (usually the most substituted) alkene is formed.

An alcohol is an organic compound with a hydroxyl (OH) functional group on an aliphatic carbon atom. Because OH is the functional group of all alcohols, we often represent alcohols by the general formula ROH, where R is an alkyl group. Most people are familiar with ethyl alcohol (ethanol), the active ingredient in alcoholic beverages, but this compound is only one of a family of organic compounds known as alcohols. The family also includes such familiar substances as cholesterol and the carbohydrates.

What Is Alcohol and What Does It Do to the Human Body?

Tertiary alcohols are eliminated easily at just above room temperature, but primary alcohols require a higher temperature. Primary alkyl halides react with aqueous NaOH or KOH to alcohols in nucleophilic aliphatic substitution. (Secondary and especially tertiary alkyl halides will give the elimination (alkene) product instead).

As a rule of thumb, an average person can eliminate 0.5 ounces (15 ml) of alcohol per hour. So, it would take approximately one hour to eliminate the alcohol from a 12 ounce (355 ml) can of beer. A more controlled elimination reaction requires the formation of the xanthate ester. Aldehydes or ketones are reduced with sodium borohydride or lithium aluminium hydride (after an acidic workup). Another reduction by aluminiumisopropylates is the Meerwein-Ponndorf-Verley reduction. Noyori asymmetric hydrogenation is the asymmetric reduction of β-keto-esters.

2: Alcohols – Nomenclature and Classification

The direct hydration using ethylene (ethylene hydration)[29] or other alkenes from cracking of fractions of distilled crude oil. Alcohols may be classified as primary, secondary, or tertiary, according to which carbon of the alkyl group is bonded to the hydroxyl group. Most alcohols are colourless liquids or solids at room temperature. Alcohols of low molecular weight are highly soluble in water; with increasing molecular weight, they become less soluble in water, and their boiling points, vapour pressures, densities, and viscosities increase. It burns with a smokeless blue flame that is not always visible in normal light. The physical properties of ethanol stem primarily from the presence of its hydroxyl group and the shortness of its carbon chain.

Because alcohol affects emotional centers in the limbic system, alcoholics can become anxious, depressed, and even suicidal. The emotional and physical effects of alcohol can contribute to marital and family problems, including domestic violence, as well as work-related problems, such as excessive absences and poor performance. When you compare men and women of the same height, weight, and build, men tend to have more muscle and less fat than women. Because muscle tissue has more water than fat tissue, a given dose or amount of alcohol will be diluted more in a man than in a woman. Therefore, the blood alcohol concentration resulting from that dose will be higher in a woman than in a man, and the woman will feel the effects of alcohol sooner than the man will. Ethanol can be produced from petrochemical feed stocks, primarily by the acid-catalyzed hydration of ethylene.