ICSE Class 10 Chemistry: Alcohols & Carboxylic Acids Notes 2026

Structure and Naming of Alcohols

• Functional group: –OH; general formula CₙH₂ₙ₊₁OH for monohydric alcohols
• Primary, secondary and tertiary alcohols based on position of –OH
• IUPAC names: methanol (CH₃OH), ethanol (C₂H₅OH), propan-1-ol

Preparation of Ethanol

• Fermentation: C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂ (yeast, 37°C, absence of air)
• Hydration of ethene: CH₂=CH₂ + H₂O → C₂H₅OH (300°C, H₃PO₄ catalyst)
• Industrial ethanol is denatured (methanol added) to prevent consumption

Properties and Reactions of Ethanol

• Oxidation: ethanol → ethanal → ethanoic acid (with K₂Cr₂O₇/H₂SO₄, orange → green)
• Combustion: C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O; clean-burning fuel
• Reaction with Na metal: C₂H₅OH + Na → C₂H₅ONa + ½H₂↑

Carboxylic Acids

• Functional group: –COOH; weak acids; formula CH₃COOH for ethanoic acid (acetic acid)
• Test: turns blue litmus red; reacts with Na₂CO₃ producing CO₂ gas
• Esterification: CH₃COOH + C₂H₅OH ⇌ CH₃COOC₂H₅ + H₂O (conc. H₂SO₄ catalyst)

Esters — Formation and Uses

• Sweet-smelling compounds; general formula RCOOR'
• Ethyl ethanoate: solvent for nail polish remover, glue, perfume
• Saponification: ester + NaOH → soap (sodium salt of acid) + alcohol

Uses of Alcohols and Acids in Industry

• Ethanol: beverages, antiseptic (70%), solvent, biofuel
• Ethanoic acid: vinegar (5–8%), preservative, manufacture of aspirin and PVC
• Methanol: fuel additive, antifreeze, solvent — highly toxic if consumed

ICSE Questions — Alcohols

• Write equation for fermentation of glucose to ethanol
• Describe the oxidation of ethanol in two stages with reagents
• State one test each to distinguish ethanol from ethanoic acid