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Chapter Analysis
Advanced29 pages • EnglishQuick Summary
Chapter 8 discusses the chemistry of aldehydes, ketones, and carboxylic acids, focusing on their chemical properties, methods of preparation, and reactions. It describes nucleophilic addition reactions for aldehydes and ketones, and oxidation reactions for aldehydes. The chapter covers the acidity of carboxylic acids and their reactions. It also details various preparation methods, such as oxidation of alcohols and Friedel-Crafts acylation for ketones.
Key Topics
- •Nucleophilic addition reactions of aldehydes and ketones
- •Oxidation of aldehydes to carboxylic acids
- •Acidity and reactions of carboxylic acids
- •Preparation methods for aldehydes, ketones, and carboxylic acids
- •Industrial applications of aldehydes, ketones, and carboxylic acids
- •Aldol condensation reactions
- •Reduction reactions of carbonyl compounds
- •Clemmensen and Wolff-Kishner reduction
Learning Objectives
- ✓Write the common and IUPAC names of aldehydes, ketones, and carboxylic acids
- ✓Describe the methods of preparation and chemical reactions of aldehydes, ketones, and carboxylic acids
- ✓Correlate the physical properties and chemical reactions with the structures of these compounds
- ✓Explain the mechanism of selected reactions involving aldehydes and ketones
- ✓Understand factors influencing the acidity of carboxylic acids
- ✓Describe the industrial uses of aldehydes, ketones, and carboxylic acids
Questions in Chapter
What is meant by the following terms? Give an example of the reaction in each case.
Answer: Cyanohydrin, acetal, semicarbazone, aldol, hemiacetal, oxime, ketal, imine, 2,4-DNP-derivative, Schiff’s base.
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Name the following compounds according to IUPAC system of nomenclature.
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Draw the structures of the following compounds.
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Write the IUPAC names of the following ketones and aldehydes. Wherever possible, give also common names.
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Predict the products formed when cyclohexanecarbaldehyde reacts with following reagents.
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Additional Practice Questions
Describe the mechanism of nucleophilic addition in aldehydes.
mediumAnswer: Nucleophiles attack the electrophilic carbon atom of the carbonyl group, leading to the formation of a tetrahedral alkoxide intermediate, which eventually forms the addition product after protonation.
Explain the difference in reactivity between aldehydes and ketones in nucleophilic addition reactions.
mediumAnswer: Aldehydes are generally more reactive than ketones due to less steric hindrance and fewer electron-donating groups, making the carbonyl carbon more electrophilic.
How does the Fehling’s test differentiate between aldehydes and ketones?
easyAnswer: Fehling's test oxidizes aldehydes to carboxylic acids, resulting in a reddish-brown precipitate, whereas ketones do not react under the test conditions.
Develop the synthetic pathway for converting a primary alcohol to an aldehyde.
hardAnswer: Primary alcohols can be oxidized to aldehydes using mild oxidizing agents such as PCC or by dehydrogenation.
What are the common applications of carboxylic acids in industry?
easyAnswer: Carboxylic acids are used in the manufacture of polymers, pharmaceuticals, and as preservatives. They are also important intermediates in the synthesis of various chemical compounds.