Waxes: Study with Video Lessons, Practice Problems & Examples

Waxes are fatty acid-based lipids formed by ester linking a long-chain fatty acid to a long-chain alcohol. They are characterized by their nonpolar, hydrophobic nature and high melting points, making them solid at room temperature. Waxes serve various functions, including waterproofing and protective coatings, commonly found in plants and products like lotions and ointments. An example is triacontinoypalmitate, a major component of beeswax, formed through dehydration synthesis of palmitic acid and triacontinol.

Which of the statements regarding waxes is FALSE?
A)  Waxes generally have melting points above room temperature.
B)  Waxes are soluble molecules in water. 
C)  Waxes are used as protective coatings against dehydration and parasites.
D)  Waxes are esters of long-chain fatty acids and long-chain alcohols.

• A. Waxes generally have melting points above room temperature.
• B. Waxes are soluble molecules in water.
• C. Waxes are used as protective coatings against dehydration and parasites.
• D. Waxes are esters of long-chain fatty acids and long-chain alcohols.

Answer: (B)

Here’s what students ask on this topic:

What are waxes in biochemistry?

Waxes in biochemistry are fatty acid-based lipids formed by ester linking a long-chain fatty acid to a long-chain alcohol. They are characterized by their nonpolar, hydrophobic nature and high melting points, making them solid at room temperature. Waxes serve various functions, including waterproofing and protective coatings, commonly found in plants and products like lotions and ointments. An example is triacontinoylpalmitate, a major component of beeswax, formed through dehydration synthesis of palmitic acid and triacontinol.

What is the chemical structure of waxes?

The chemical structure of waxes consists of a long-chain fatty acid esterified to a long-chain alcohol. The general formula can be represented as:

$R-\mathrm{COO}-\mathrm{R\text{'}}$

where $R$ is the long-chain fatty acid and $\mathrm{R\text{'}}$ is the long-chain alcohol. For example, in beeswax, the fatty acid palmitic acid (C₁₆H₃₂O₂) is esterified to the alcohol triacontanol (C₃₀H₆₂O), forming triacontinoylpalmitate.

What are the functions of waxes in nature?

Waxes serve several important functions in nature. They provide waterproofing, helping to keep water out and retain moisture within organisms. For example, plants produce waxes on their leaves to prevent dehydration and protect against environmental stress. Waxes also act as protective coatings, shielding surfaces from physical damage and microbial attack. Additionally, they are used in various products like lotions, ointments, and polishes due to their hydrophobic properties and ability to form a protective barrier.

Why are waxes hydrophobic and insoluble in water?

Waxes are hydrophobic and insoluble in water due to their long hydrocarbon chains, which are nonpolar. These nonpolar tails dominate the overall structure, making waxes nonpolar and thus unable to interact favorably with water molecules, which are polar. Any polar groups present in waxes are weak and are overpowered by the extensive nonpolar regions, reinforcing their hydrophobic nature and insolubility in water.

What is the role of waxes in commercial products?

In commercial products, waxes play a crucial role due to their hydrophobic and protective properties. They are commonly used in lotions and ointments to create a barrier on the skin, preventing moisture loss and providing a protective layer. Waxes are also used in polishes to give surfaces a shiny, protective coating. Their high melting points and solid state at room temperature make them ideal for these applications, ensuring durability and effectiveness.