What functional group is present in carboxylic acids?
Carboxyl
The –COOH group contains both a carbonyl and hydroxyl group.
What type of compounds are formed when a carboxylic acid reacts with an alcohol?
Esters
The reaction is known as esterification.
Fill in the blanks:
Carboxylic acids react with carbonates to release _______ _______ gas.
carbon dioxide
This reaction forms CO2, water and a salt.
True or False:
Carboxylic acids are strong acids in aqueous solution.
False
They are weak acids and only partially dissociate.
What catalyst is commonly used in esterification reactions?
Concentrated sulfuric acid
It acts as an acid catalyst and dehydrating agent.
True or False:
Esters often have distinctive fruity smells.
True
This is why they are used in perfumes and food flavourings.
Fill in the blank:
Esters can be hydrolysed in alkaline conditions to produce an alcohol and a _______ of a carboxylic acid.
salt
The salt forms because the acid reacts with the alkali.
What type of molecules are vegetable oils and animal fats chemically classified as?
Esters
They are esters formed from glycerol and fatty acids.
True or False:
Soap is produced by alkaline hydrolysis of fats and oils.
True
This process is called saponification.
Fill in the blank:
Hydrolysis of fats in alkaline solution produces glycerol and _______.
soap
Soap consists of salts of long-chain carboxylic acids.
What substance reacts with vegetable oils to produce biodiesel?
Methanol
A catalyst is used to form methyl esters.
What type of compounds make up biodiesel?
Methyl esters
These esters are derived from long-chain fatty acids.
What functional group is present in acyl chlorides?
Acyl chloride
The functional group has the structure –COCl.
What functional group links two acyl groups together in acid anhydrides?
Anhydride linkage
The structure contains –CO–O–CO–.
Fill in the blank:
A primary amide contains the functional group _______.
–CONH2
Amides contain a carbonyl group attached to nitrogen.
True or False:
Acyl chlorides are highly reactive towards nucleophiles.
True
The C–Cl bond is easily attacked due to the electron-withdrawing chlorine.
What type of reaction occurs when acyl chlorides react with nucleophiles?
Nucleophilic addition–elimination
The nucleophile adds to the carbonyl carbon then a leaving group is eliminated.
True or False:
Acyl chlorides react with water to form carboxylic acids and HCl.
True
The reaction also produces hydrogen chloride gas.
Fill in the blank:
Reaction of an acyl chloride with an alcohol produces an _______.
ester and HCl
The alcohol replaces the chlorine atom.
What product forms when an acyl chloride reacts with ammonia?
Amide
Ammonia acts as a nucleophile and replaces the chloride. This reaction also produces HCl gas.
True or False:
Primary amines reacting with acyl chlorides produce N-substituted amides.
True
The –NH2 group acts as the nucleophile.
Fill in the blank:
In nucleophilic addition–elimination reactions, the nucleophile first attacks the _______ carbon.
carbonyl
This forms a tetrahedral intermediate.
Why is ethanoic anhydride often preferred to ethanoyl chloride in aspirin manufacture?
Safer and less corrosive as it doesn’t produce toxic HCl gas
It produces fewer hazardous by-products.
What type of molecule acts as the nucleophile in acylation reactions?
Electron pair donor
Examples include water, alcohols and amines.
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2.1 Atoms, Compounds, Molecules & Equations50
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2.2 Amount of Substance47
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2.3 Acid–Base69
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2.4 Electrons, Bonding and Structure90
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3.1 Periodicity22
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3.2 Group 2 and Halogens55
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3.3 Qualitative Analysis39
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3.4 Enthalpy Changes62
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3.5 Reaction Rates (Qualitative)55
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3.6 Equilibrium (Qualitative)24
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4.1 Basic Organic Chemistry Concepts42
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4.2 Hydrocarbons85
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4.3 Alcohols and Haloalkanes79
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4.4 Organic Synthesis12
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4.5 Analytical Techniques (IR & MS)36
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5.1 Reaction Rates (Quantitative)24
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5.2 Equilibrium (Quantitative)12
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5.3 pH and Buffers15
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5.4 Enthalpy, Entropy & Free Energy27
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5.5 Redox & Electrode Potentials63
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5.6 Transition Elements95
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6.1 Aromatic Compounds29
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6.2 Carbonyl Compounds20
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6.3 Carboxylic Acids & Esters25
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6.4 Nitrogen Compounds102
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6.5 Polymers24
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6.6 Organic Synthesis (Advanced)20
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6.7 Chromatography & Spectroscopy (NMR)26
