Carboxylic Acid

Reactions

Contents

• Carboxylic Acids• Physical Properties• Preparation of Carboxylic Acids• Reactions of Carboxylic Acids

– …With metals– …With bases– …With carbonates– …With Alkalis– …Esterification

• Summary

Carboxylic Acids

• The functional group is –COOH or

• They are named by taking the ‘e’ from the stem of the alkane and adding ‘–oic acid’ for the suffix

• They are found throughout nature– Citrus fruits– Rhubarb leaves– Sting of ants

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Physical Properties

• Very soluble in solvents

• Soluble in water due to hydrogen bonding

• As mass increases, solubility decreases

• Boiling point increases as size increases due to more van der Waals

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Preparation of Carboxylic Acids• There are several ways to prepare carboxylic acids,

the following list corresponds to the equations below1. Oxidation of aldehydes

2. Hydrolysis of esters

3. Hydrolysis of acyl chlorides

4. Hydrolysis of nitriles

5. Hydrolysis of amids

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Reactions of Carboxylic Acids…

• They are weak monobasic acids

• Take part in the typical acid reactions

• Salts formed are known as caboxylates

• The carboxylate contains a carboxylate ion

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…With Metals

• Produces a salt and hydrogen

…With Bases

• Produces salt and water

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…With Carbonates

• Produces a salt, carbon dioxide and water

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…With Alkalis• Produces a salt (equation 1)• The acid can be freed from the salt by reacting

with a stronger aid (equation 2)

Esterification

• Reagents: Alcohol + acid catalyst (conc. H₂SO₄)

• Conditions: Reflux• Equation:

• Concentrated is used because it is a dehydrating agent that will help remove the water

• This will increase the yield of ester

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Summary

AlcoholEster + Water

AlcoholEster + Water

Weak AcidProton donor

Weak AcidProton donor

CarbonateSalt + Water

+CO₂

CarbonateSalt + Water

+CO₂

MetalSalt + H₂Metal

Salt + H₂

BaseSalt + Water

BaseSalt + Water

CarboxylicAcid

CarboxylicAcid

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