3.3.9 Carboxylic acid and derivatives

Question 1

What is the functional group for a carboxylic acid ?

Answer 1

COOH

Question 2

Are carboxylic acids weak or strong and what happens when they are in water ?

Answer 2

They are weak acids and in water they partially dissociate into a carboxylate ion (Lose H from COOH) and a H+ ion

Question 3

What is produced when carboxylic acids react with carbonates ?

Answer 3

Carboxylate salt, Carbon dioxide and water

Question 4

What is an esterification reaction?

Answer 4

Making of an ester by combining carboxylic acid and alcohol

Question 5

What catalyst is used in an esterification reaction ?

Answer 5

Strong acid catalyst (lots of H+) for example H2SO4

Question 6

As carboxylic acids are weak acids where does the position of the equilibrium lie ?

Answer 6

Equilibrium lies to the left as it dissociates poorly

Question 7

How are esters named ?

Answer 7

The first bit is the alkyl (alcohol) group and the second is the carboxylic acid. For example ethylpropanoate

Question 8

Give some commercial uses of esters

Answer 8

• Perfumes and food colourings (sweet smelling)
• Solvents (polar so good for glue sticks)
• Plasticisers (flexible during polymerisation)

Question 9

Esters can be hydrolysed. What does hydrolysed mean ?

Answer 9

Split using water

Question 10

What are the products of acid hydrolysis ?

Answer 10

Carboxylic acid and alcohol

Question 11

What are the conditions and reagents needed for acid hydrolysis ?

Answer 11

• Sulfuric or hydroclauric acid can be used
• Under reflux
• H2O

Question 12

What are the products of base hydrolysis ?

Answer 12

Carboxylate ion and water

Question 13

What are the conditions and reagents needed for base hydrolysis ?

Answer 13

• Sodium hydroxide
• Under reflux
• OH- ion

Question 14

What is the IUPAC name for glycerol ?

Answer 14

Propane-1,2,3-Triol

Question 15

What is produced when glycerol and fatty acids are reacted together ?

Answer 15

An ester that can be used to make fats and oils

Question 16

What is an unsaturated fatty acid ?

Answer 16

Fatty acid with one or more double bond

Question 17

Give an example of a unsaturated oil ester

Answer 17

Vegetable oil, not straight chains means they can’t pack close together and low VDWs

Question 18

Give an example of a saturated fat ester

Answer 18

Animal fats, straight chains so can pack close together so have higher VDWs

Question 19

What are the products when a fat and sodium hydroxide are reacted together ?

Answer 19

Glycerol and sodium salt (soap)

Question 20

How do you make soap ?

Answer 20

Fat and conc sodium hydroxide and heat

Question 21

How can biodiesel be made ?

Answer 21

By reacting oils with methanol and a potassium hydroxide catalyst

Question 22

What is the functional group of an Acyl chloride ?

Answer 22

-COCl

Question 23

What is produced when acyl chlorides react with water ?

Answer 23

Carboxylic acid and Hal

Question 24

What is produced when acyl chlorides react with ammonia ?

Answer 24

Amide and HCl

Question 25

What is produced when acyl chlorides react with alcohol ?

Answer 25

Ester and HCl

Question 26

What is produced when acyl chlorides react with primary amines ?

Answer 26

N-substituted amide and HCl

Question 27

What is an acid anhydride ?

Answer 27

Made from two carboxylic acids that are the same

Question 28

What is produced when an acid anhydride reacts with water ?

Answer 28

2 Carboxylic acids

Question 29

What is produced when an acid anhydride reacts ammonia ?

Answer 29

An amide and a carboxylic acid

Question 30

What is produced when an acid anhydride reacts with alcohol ?

Answer 30

An ester and a carboxylic acid

Question 31

What is produced when an acid anhydride reacts with primary amines ?

Answer 31

N-substituted amide and carboxylic acid