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Identification of primary, secondary and tertiary alcohols

Because alcohols contain hydroxyl groups, there is a distinction between the two types of alcohol. Alcohols also differ in their physical and chemical properties depending on where the hydroxyl group is located on the molecule. Alcohol can be classified into three categories. There are three forms of alcohol: Primary, Secondary, and Tertiary alcohols. Primary alcohols are the most common. The location of the carbon atom in an alkyl group in relation to the hydroxyl group is used to classify the group. At room temperature, a number of alcohols are described as colourless liquids or even solids, depending on the species. Water solubility is determined by the molecular weight of an alcohol. The lower its solubility, the higher its density and viscosity. The higher its molecular weight, the higher its density, boiling point, vapour pressure, and viscosity.

Alcohol

Alcohols are organic compounds that are defined by the presence of one, two, or more hydroxyl groups (OH) that are connected to the carbon atom in an alkyl group or hydrocarbon chain. Alcohols can be classified into three types: ethers, ether-like compounds, and ether-like compounds.

This class of alcohols is regarded to be derivatives of water in which one of the hydrogen atoms has been replaced by an alkyl group, which is commonly denoted by the symbol R in an organic structure, in which case they are considered to be ethers. Alcohol is available in a variety of shapes and forms as well.

Alcohols are recognised to be one of the most often occurring organic compounds, accounting for approximately one-third of all organic compounds. These are used as sweeteners, in the manufacturing of perfumes, and in the process of synthesising other compounds. Some of these are widely produced in organic chemicals used in a variety of industries, while others are used in the process of synthesising other compounds.

Main Types of Alcohols

Alcohols are distinguished by the presence of a hydroxyl group bonded to their carbon atoms. The placement of this hydroxyl group, as well as the nature of the alcohol, will influence its physical and chemical properties. There are three different kinds of alcohol. 

Alcohols are divided into three categories: primary, secondary, and tertiary alcohols.

The classification is done based on the position of the carbon atom of an alkyl group in relation to the hydroxyl group on the molecule. Almost all alcoholic beverages are known to be colourless liquids or even to behave as solids when exposed to room temperature conditions. Alcohols with a low molecular weight are considered to be very soluble in water; but, as their molecular weight increases, they tend to become less soluble in water and their vapour pressures, boiling temperatures, densities, and viscosities increase.

Primary Alcohols

One type of alcohol that is classified as primary alcohol is one in which the carbon atom of the hydroxyl group (OH) is connected to only one type of alkyl group. Methanol (propanol), ethanol, and other primary alcohols are examples of this class of compounds. In this case, the intricacy of the alkyl chain has nothing to do with the classification of any alcohol that is deemed to be primary. The presence of only one bond between a –OH group and an alkyl group is the characteristic that distinguishes any alcohol as a primary alcohol.

Secondary Alcohols

Secondary alcohols are those in which the carbon atom of the hydroxyl group is connected to two alkyl groups on either side of the hydroxyl group, forming a double bond. The two alkyl groups that are present may be structurally same or may possibly be structurally distinct.

Tertiary Alcohols

Tertiary alcohols are ones that contain hydroxyl groups bonded to the carbon atoms that are linked to three alkyl groups. The physical properties of these alcohols are mostly determined by their structural composition. Because of the existence of this -OH group, alcohols are capable of forming hydrogen bonds with the atoms in their immediate vicinity. Because of the weak nature of the bonds formed, the boiling points of alcohols are greater than those of their alkane counterparts.

Uses of Alcohols

Alcohols can be used in a variety of ways. Some examples are provided below.

  • Alcohols are ingested in the form of beverages, with the alcohols containing 30–40 percent ethanol by volume in the case of spirits.
  • These are employed as an anti-freezing agent in a solution comprising ethylene glycol dissolved in water, which is combined with other ingredients.
  • Alcohol ethanol is utilised as an antiseptic agent in the medical field.
  • Alcohols such as methanol, which are utilised as fuel in internal combustion engines, are examples of such substances.
  • In the sphere of medicine, a number of them are employed as preservatives for specimens in laboratories, and others are used as disinfectants.

Conclusion

Alcohols can be classified according to which carbon atom is attached to the hydroxyl group, according to one method of classification. If this carbon atom is primary (1°, meaning that it is only bonded to one other carbon atom), the chemical is classified as a primary alcohol. A secondary alcohol is characterised by the presence of the hydroxyl group on a secondary (2°) carbon atom that is bound to two additional carbon atoms. Tertiary alcohols are compounds in which a hydroxyl group (OH) is connected to a saturated carbon atom that has three additional carbon atoms attached to it. Tertiary alcohols are compounds that have three carbon atoms bonded to them. 

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What is the difference between primary, secondary, and tertiary alcohols?

ANS. When the carbon atom with the -OH group attached is connected directly to two alkyl groups, this is referred to...Read full

What is the best way to tell if something is a secondary alcohol?

ANS. The presence of a colour change with the acidified potassium dichromate solution and the absence of a colour ch...Read full

Why are tertiary alcohols more reactive than primary alcohols?

ANS. Tertiary alcohols are more reactive than primary alcohols due to the higher amount of alkyl groups in the compo...Read full

Why do primary alcohols deteriorate at a greater rate than secondary alcohols?

ANS. Alcohols are classified as primary if their hydroxyl group is located at the carbon atom that is the first in t...Read full

What causes primary alcohols to have greater blood pressure?

ANS. Hydrogen bonds. The van der Waals dispersion forces are the only intermolecular interactions that exist in alka...Read full