Students who are about to appear in the O-Level Chemistry exam must be familiar with the division of topics into organic and inorganic chemistry sections. When studying organic chemistry, one of the first topics you’ll learn about is alcohol. These molecules have a wide range of applications, both in industry and in everyday life. Let’s take a look at some of the most important physical properties of alcohol. We’ll also explore how these properties can be used to identify different types of alcohol. 

All About Alcohols- Organic Chemistry

What are Alcohols?

Alcohols are a type of organic compound that contains the hydroxyl functional group. This group consists of a carbon atom bonded to a hydrogen atom, with a hydroxyl group (-OH) attached. They are named by replacing the -e at the end of the parent alkane name with -ol. For example, ethanol is the alcohol form of ethane. The alcohol chemical formula is CnH2n+1OH. 

Types of Alcohols

Alcohol can be divided into three groups: primary, secondary, and tertiary. 

• Primary alcohols have the hydroxyl group bonded to a primary carbon atom.
• Secondary alcohols have the hydroxyl group bonded to a secondary carbon atom.
• Tertiary alcohols have the hydroxyl group bonded to a tertiary carbon atom.

Alcohols are known as leans if they have 6 or fewer carbons in their backbone, and as branched if they have more than 6 carbons in their backbone. They are bases and can react with acids to form esters. They have high solubility in water and a high boiling point due to the hydrogen bonding between molecules. 

Today, a variety of industries, including pharmaceuticals, cosmetics, and cleaning agents use alcohol.

The Physical Properties of Alcohol

Alcohols have a wide range of physical properties, depending on the size and structure of the molecule. 

1. Alcohols are generally less volatile than water and have higher boiling points than similar molecules without the hydroxyl group. It occurs due to the hydrogen bonding between molecules of alcohol. 
2. Solubility is another important physical property of alcohol. Alcohols are also polar molecules which means that they can dissolve in water and other polar solvents. 
3. They are typically less dense than water and have lower melting and boiling points than other molecular compounds with similar structures. 
4. The molecular weight and degree of branching also affect the physical properties of alcohol. 

The Chemical Properties of Alcohols

Alcohols have several distinct chemical properties. 

1. They are polar molecules, meaning that they have a slightly positive charge at one end and a slightly negative charge at the other. This gives them the ability to form hydrogen bonds with other molecules, which is why alcohols tend to be soluble in water. 
2. Alcohols also have a higher boiling point than most other organic compounds, due to the strong intermolecular forces between molecules. 
3. Additionally, alcohols can undergo reduction reactions which means they can be converted into other compounds by adding electrons. 
4. In the presence of a catalyst, alcohols can react with a carboxylic acid to produce an ester. C₂H₅OH + C₂H₃COOH →C₄H₈O₂ + H₂O

This chemical process is known as esterification. 

All these properties make alcohols versatile compounds that can be used in a variety of applications.

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