Carboxylic Acids and Derivatives

• Carboxylic acids and their derivatives all contain a C=O double bond
• Match the compound type with its general formula:

  Carboxylic acids ↔️ R-C-OH

  Esters ↔️ R-C-OR'

  Acyl chlorides ↔️ R-C-Cl

  Amides ↔️ R-C-NH₂
• The general formula for carboxylic acids is CnH2nO2
• Arrange the following compounds in order of increasing boiling point:

  1️⃣ Butane

  2️⃣ Propan-1-ol

  3️⃣ Ethanoic acid
• Why is hydrogen bonding stronger than van der Waals forces?

  Polarity
• Carboxylic acids form dimers due to hydrogen bonding.
• What makes carboxylic acids with low molecular mass soluble in water?

  Hydrogen bonding
• An acid is defined as a substance that donates H+ ions.
• Carboxylic acids are strong acids because they fully ionize in solution.

  False
• Match the reaction type with its products:

  Acid + Base ↔️ Salt + Water

  Acid + Carbonate ↔️ Salt + Water + CO₂

  Acid + Metal ↔️ Salt + Hydrogen
• What gas is released when a carboxylic acid reacts with sodium hydrogencarbonate?

  Carbon dioxide
• The general formula for esters is CnH2nO2
• Match the parent alcohol and acid with the ester name:

  Ethanoic acid + Methanol ↔️ Methyl ethanoate

  Methanoic acid + Ethanol ↔️ Ethyl methanoate
• Esters and carboxylic acids are functional group isomers of one another.
• What is a common property of esters that makes them useful in perfumes?

  Sweet smell
• The preparation of esters involves a condensation reaction.
• Arrange the steps for preparing an ester from a carboxylic acid and an alcohol:

  1️⃣ Add alcohol to carboxylic acid

  2️⃣ Add conc H₂SO₄ as a catalyst

  3️⃣ Heat the mixture

  4️⃣ Condensation occurs
• What is the definition of hydrolysis in chemistry?

  Breaking bonds using water
• Acid hydrolysis of an ester produces a carboxylic acid and an alcohol.
• What are the products of alkaline hydrolysis of an ester?

  Carboxylate salt and alcohol
• What two types of molecules are combined to form a triglyceride?

  Glycerol and fatty acids
• Fats are solid at room temperature because they often contain saturated fatty acids.
• Triglycerides can be hydrolysed under alkaline conditions to form glycerol and fatty acid salts.
• What is the primary use of the sodium salts of fatty acids formed during triglyceride hydrolysis?

  Soaps
• What type of compound is biodiesel made from?

  Methyl esters
• The process used to produce biodiesel is called transesterification.
• Arrange the steps for manufacturing biodiesel:

  1️⃣ React vegetable oils with methanol

  2️⃣ Add KOH as a catalyst

  3️⃣ Transesterification occurs

  4️⃣ Biodiesel and glycerol are formed
• Carboxylic acids react with alcohols in the presence of an acid catalyst to form esters.
• What is acylation in chemistry?

  Introduction of the acyl group
• Compounds with the acyl group in their structure are called acid derivatives.
• Match the acid derivative with its example:

  Acyl chloride ↔️ Ethanoyl chloride

  Acid anhydride ↔️ Propanoyl anhydride
• The carbonyl bond in acid derivatives is polar.
• What is a nucleophile in chemistry?

  Electron pair donor
• Water is a nucleophile that reacts with acid derivatives by donating an electron pair
• Steps in the reaction of an acyl chloride with water:

  1️⃣ The nucleophile, water, is added

  2️⃣ The double bond in the acyl chloride breaks

  3️⃣ A tetrahedral intermediate forms

  4️⃣ HCl is eliminated

  5️⃣ The double bond reforms
• Acyl chlorides react with water to form acidic solutions with a low pH.
• What does a curly arrow represent in a reaction mechanism?

  Movement of electron pair
• The reaction mechanism between an acyl chloride and water is called nucleophilic addition-elimination
• Acyl chlorides react with ammonia to form amides.
• Match the acyl chloride reaction with its product:

  Water ↔️ Carboxylic acid

  Ammonia ↔️ Amide

  Alcohol ↔️ Ester