Problem 68 - A Complete Resource Book in Chemistry for JEE Main

Question

The group present in waxes are (a) acid group (b) ester group (c) alcoholic group (d) ether group

Step-by-Step Solution

Answer

The group present in waxes is the ester group.

Step 1: Understand the Question

We are asked to identify the group present in waxes from the given options: acid group, ester group, alcoholic group, and ether group.

Step 2: Review the Structure of Waxes

Waxes are esters formed from long-chain fatty acids and long-chain alcohols. This is crucial in determining the functional group present.

Step 3: Compare with Given Options

Compare the knowledge from Step 2 with the options provided: - The acid group (carboxylic acids) is not the primary functional group in waxes. - The ester group is the group formed in waxes. - Alcoholic groups are part of the structure, but not the primary functional group. - Ether group is not relevant to waxes.

Step 4: Select the Correct Option

The correct functional group present in waxes, based on their formation from fatty acids and alcohols, is the ester group.

Key Concepts

Ester Group

The ester group is a crucial component in the chemistry of waxes. It is a type of functional group found in organic compounds where a carbon atom is double-bonded to an oxygen atom and the same carbon atom is also singly bonded to another oxygen atom, which is further connected to another carbon chain. This can be represented in the structural formula as \( RCOOR'^\ \). Ester groups are formed through the reaction of carboxylic acids and alcohols. In the case of waxes, these esters are created by the combination of long-chain fatty acids and long-chain alcohols. This combination results in a stable and non-polar compound that is often solid at room temperature. Understanding the ester group is key to identifying why waxes possess their unique properties, such as their hydrophobic nature and impermeability to water. It is because the ester linkage in waxes does not mix with water that they are able to function as protective coatings and barriers in nature.

Organic Chemistry

Organic chemistry is the branch of chemistry that studies the structure, properties, composition, reactions, and preparation of carbon-containing compounds. These range from simple molecules like methane to complex polymers and biological compounds. Key Features of Organic Chemistry:

• Focuses on carbon-based molecules which make up a majority of compounds in the world.
• Includes a variety of compounds that contain other elements such as hydrogen, oxygen, nitrogen, sulfur, and halogens.
• Explores functional groups, which are specific groupings of atoms within molecules that have their characteristic chemical reactions.
• Emphasizes the study of chemical reactions and understanding the synthesis and breakdown of compounds.

Organic chemistry is fundamental to producing materials such as plastics, medicines, and dyes, and understanding biological processes. It's also essential in the study of waxes, as it helps to understand the molecular composition and chemical reactions that form these substances.

Functional Groups

Functional groups are specific groups of atoms within molecules that have a consistent and predictable chemical behavior, regardless of the molecule they are a part of. Recognizing these groups is essential for understanding the chemical properties and reactions of organic molecules.In chemistry, a few important functional groups include:

• Hydroxyl Group \((\text{-OH})\): Found in alcohols, making them polar and water-soluble.
• Carboxyl Group \((\text{-COOH})\): Found in carboxylic acids, contributing acidity.
• Ester Group \((\text{-COOR})\): Found in esters, defining a key feature of waxes.
• Amino Group \((\text{-NH}_2)\): Present in amines and amino acids, increasing solubility and reactivity.

Functional groups allow chemists to predict how a molecule might react in various conditions. In the context of the exercise, the ester group plays a pivotal role within waxes. Knowing the presence of ester groups helps explain the characteristics and uses of waxes, such as their role in waterproofing and protection due to their non-polar nature.