Different types of alcohol
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 are known as polyhydric.
The monohydric is the simplest alcohol with the general molecular formula
CnH2n+2O or CnH2n+1OH
The aromatic and aliphatic alcohol
Thus aliphatic alcohols are compounds containing hydroxyl groups in the side chain of the alkyl group. Thus these types are the alkyl derivative of alcohol.
Examples of the aliphatic alcohol
- Methanol, ethanol, propanol, butanol, isobutanol, etc are examples of monohydric alcohols because it contains only one hydroxyl group.
- But ethylene glycol, trimethylene glycol, pentamethylene glycol, isobutene glycol are dihydric types of aliphatic alcohols because it contains two alcoholic groups.
- The only important trihydric aliphatic alcohol is glycerol or propane-1-2-2-triol because it contains 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.
Examples of aromatic alcohol
Types of monohydric alcohols
Monohydric alcohols are further classified into, primary, secondary, and tertiary. Hence This classification based on the position of the alcoholic attached to the alkyl groups.
If the alcoholic group attached to the alpha, beta, and gamma carbon atom, then these alcohols are known as primary secondary and tertiary respectively.
The common name of alcohols
Different types of simpler monohydric alcohols are known by their trivial names. Thus this type of naming obtained by alcohol is a derivative of the alkyl group attached to the hydroxyl or alcoholic group.
methyl ethyl methanol
Uses of alcohol in daily life
It is commercially very important compounds and largely uses in alcoholic beverage as wine and beer.
- Hence it used as a solvent for paints, varnishes, shellac, celluloid, and cement industry.
- When ethanol mixed with small amounts of methanol forms methylated spirit. This mixture used as an automobile antifreeze mixture, remove ink from various kind of surface.
- Alcohols used for manufacturing dyes and drugs, perfumes, etc and ethanol also used as an alternate fuel of the motor vehicle.
- Phenol used as an antiseptic and disinfectant. It also uses for the preparation of drugs and bakelite.
Alcoholic fermentation reaction
Fermentation is the earliest process for the preparation of ethanol. But this process still uses for the manufacture of beer, wine, and brandy. The common materials used for this process are wheat, barley or potato.
Hence the mashed materials boiling at 500C for one hour. But the melt contains the enzyme diastase, which converted starch into maltose and sugar by hydrolysis.
The liquid-cooled to 3000C and fermented with yeast for 1-3 days. But yeast contains various enzymes, among which maltase converts maltose into glucose and zymase. But zymase further converted glucose into ethanol.
The CO2 recovered and sold as a by-product. But fermented liquor which contains 6 -10 percent of alcohol uses as the manufacture of wine, beer, brandy or other food beverage.