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Definition, Types, Formula, Uses

Different Types of Alcohol in Chemistry

Types of alcohol uses for the manufacture of drinks or beer, vodka, brandy is ethyl alcohol or ethanol but monohydric, polyhydric, aromatic, and aliphatic alcohols used in different alcoholic content like food beverages and drug preparation. Alcohol is the isomers of ether or hydroxyl derivative of hydrocarbon prepared from alkene with specific heat and dilute sulfuric acid under pressure. According to the number of functional or alcoholic groups, these organic compounds in chemistry are classified as, Monohydric Dihydric, Trihydric, Polyhydric alcohol. The lower members of alcohol are liquids and lees volatile due to association through hydrogen bonding extending over a chain of molecules but higher members are solid and almost orderless.

The lower alcohols are very soluble in water and solubility diminishes as molecular weight increases because the oxygen atom of the hydroxyl group forms hydrogen bonding with water molecules. Alcohol withdrawal hydrogen atom by the action of metals shows acid properties but they do not affect the pH level of the water solution since they are weaker acid than water. Therefore, the alkoxides beings hydrolyzed by water, and for this reason, ethoxide is the stronger base than the hydroxide ion.

Different types of alcohols like monohydric or polyhydric alcohol and uses alcoholic content

Infrared spectrum studies of hydroxyl groups in alcohol show they absorbed electromagnetic spectrum radiation with the frequency from 3650 to 3580 cm-1 and this is true only if there is no hydrogen bonding. Therefore, intermolecular hydrogen bonding in alcohols produces absorption in the region from 3550 to 3230 cm-1.

Monohydric and Polyhydric Alcohols

Monohydric alcohols contain one alcoholic group and dihydric and trihydric contain two or three alcoholic groups. But the alcohols contain four or more than four alcoholic groups called polyhydric alcohols. The monohydric alcohols are the simplest with the general molecular formula, CnH2n+2O or CnH2n+1OH.

Aromatic and Aliphatic alcohols

But other types of classification of alcohol are given according to the attached alcoholic group to the aromatic or aliphatic Hydrocarbon. Hence these alcohol names as aliphatic and aromatic alcohols. Aliphatic alcohols are compounds containing hydroxyl groups in the side chain of the alkyl group but aromatic alcohols are compounds containing alcoholic groups directly attached to the nucleus of the benzene ring.

Types of Aliphatic alcohol

Methanol, ethanol, propanol, isopropyl alcohol, butanol, isobutanol, etc are examples of monohydric alcohols because these contain only one hydroxyl group. But ethylene glycol, trimethylene glycol, pentamethylene glycol, isobutene glycol are dihydric types of aliphatic alcohols. These chemicals contain two alcoholic groups. The only important trihydric aliphatic organic compound is glycerol or propane-1-2-2-triol because these contain three alcoholic groups. Glycerol occurs in almost all animals and vegetable oils. Hence D-sorbitol, D-mannitol, and dulcitol are the polyhydric aliphatic alcohols that occur naturally contain more than three hydroxyl groups.

Types of Aromatic Alcohol

Aromatic alcohols are also classified as monohydric, dihydric, trihydric, and polyhydric phenols, according to the hydroxyl group attached to the benzene ring. Therefore, phenol, catechol (o-dihydroxybenzene), Resorcinol (m-dihydroxybenzene)quinol (p-dihydroxy benzene ) are examples of these types of alcohols.

Monohydric Alcohol Formula

Monohydric alcohols are further classified according to structural formula as primary, secondary, and tertiary alcohol. Hence the classification is based on the position of the alcoholic group attached to the alkyl. If the alcoholic group is attached to the alpha, beta, and gamma carbon atom, then these alcohols are known as primary secondary, and tertiary respectively.

Chemical Names and Formula

Different types of simpler monohydric alcohols are known by their trivial names for learning chemistry. This type of naming is obtained from the alcohol formula which is the chemical derivative of the alkanes or paraffin like methane, ethane, propane, etc attached to the hydroxyl or alcoholic group. For examples, methanol, CH3OH, n-propanol, CH3CH2CH2OH, iso-propanol, CH3CH(OH)CH3, t-butanol, (CH3)3COH. But other types of naming by considering the alcohols as the derivative of methanol. For example, CH3CH2CH3OH, ethyl methanol, and CH3CH2CH(OH)CH3, methyl ethyl methanol.

Common Uses of Alcoholic Content

Alcohols are the commercially essential organic chemical compounds and common types of alcohol content use mainly in alcoholic wine beverages like vodka, beer, whisky, etc. Alcohol is used as a solvent for paints, varnishes, shellac, celluloid, and cement plant. When ethyl alcohol or ethanol mixed with small amounts of methanol forms methylated spirit which mixture used as an automobile antifreeze mixture, remove ink from various kinds of surfaces. Alcohol uses for manufacturing dyes and antibiotics drugs, perfumes, etc, and ethanol is also used as an alternate fuel for the motor vehicle or energy generation (renewable energy) process. Common alcohols like Phenol, methanol, ethanol uses as an antiseptic, alcohol-based hand sanitizer, and preparation of antibiotics drugs or bakelite.

Preparation of Alcohol by Fermentation

Fermentation in the environment is the earliest method for the preparation of ethyl alcohol by the chemical catalyst and uses for the manufacture of different types of drinks brands like beer, wine, whisky, and brandy. The common materials used for these chemical equilibrium reactions are wheat, barley, or potato. The mashed materials boiling at 50 °C for one hour. But the melt contains the enzyme diastase effects on starch to convert maltose and sugar by hydrolysis in the alcohol preparation process, 2(C6H10O5)n + nH2O → nC12H22O11.

The liquid is cooled to 300 °C and fermented with yeast for 1-3 days. Yeast contains various enzymes, among which maltase converts maltose into glucose and zymase. But zymase further converted glucose into ethanol (C2H5OH). The carbon dioxide gas recovered and sold as a by-product. The fermented liquor which contains 6 -10 percent alcohol uses for the manufacture of wine, beer, brandy, or other types of food beverage.