Chapter 8 · Chemistry
Vinegar to Nylon: Uses of Carboxylic Acids
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Where carboxylic acids are used: formic acid in industry, acetic acid as a solvent and vinegar, adipic acid for nylon-6,6 through amide links, sodium benzoate as a food preservative, fatty-acid salts as soap, and aspirin as a medicine.
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Aldehydes, Ketones and Carboxylic Acids: The Whole Chapter in One MinuteThe chapter in one place: the polar, planar C=O group; how aldehydes and ketones are made; nucleophilic addition; aldol and Cannizzaro; Tollens' and Fehling's tests; and why carboxylic acids are acidic.Chemistry
Key points
- Formic acid: rubber, textile, dyeing, leather and electroplating industries.
- Acetic acid: a solvent, and vinegar in the food industry.
- Adipic acid + hexamethylenediamine → amide links –CO–NH– (water lost) → nylon-6,6.
- Sodium benzoate: food preservative; benzoic esters: perfumes; sodium salts of fatty acids = soap; aspirin is acetylsalicylic acid.
Uses at a glance
| Compound | Use |
|---|---|
| HCOOH (formic acid) | rubber, textile, dyeing, leather, electroplating |
| CH₃COOH (acetic acid) | solvent; vinegar |
| HOOC(CH₂)₄COOH (adipic acid) | nylon-6,6 |
| C₆H₅COONa (sodium benzoate) | food preservative |
| benzoic esters | perfumery |
| sodium salts of fatty acids | soaps and detergents |
| acetylsalicylic acid | aspirin: pain and fever |
Soap in two parts
- Long hydrocarbon tail: non-polar, dissolves grease.
- –COO⁻ head: ionic, attracted to water.
- Together they carry grease into water.
Quick quiz
5 questions. Choose an answer for each, then submit to see your score and the explanations.
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