3.6 Alcohols, carboxylic acids and esters

Question 1

How are carboxylic acids formed?

Answer 1

By the oxidisation of alcohols

Question 2

What are the two ways that alcohols can be oxidised?

Answer 2

1. Through microbial action

2. Reacting with a chemical oxidising agent

Question 3

What is an example of a chemical oxidising agent?

Answer 3

Potassium Dichromate

Question 4

What acid is the main part of vinegar?

Answer 4

Ethanoic acid

Question 5

What sort of pH do carboxylic acids have and why?

Answer 5

High pH values for acids. This is because the only partially ionise.

Question 6

What substance is formed by the oxidisation of ethanol?

Answer 6

Ethanoic acid

Question 7

Why does the fermentation of beer and wine have to take place in the absence of air?

Answer 7

The oxygen in air would react with the acids to cause a carboxylic acid to form.

Question 8

What is the formula of methanoic acid?

Answer 8

HCOOH

Question 9

What is the formula of ethanoic acid?

Answer 9

CH3COOH

Question 10

What is the formula of propanoic acid?

Answer 10

C2H5COOH

Question 11

What does ethanoic acid smell of?

Answer 11

Vinegar

Question 12

What colour does universal indicator paper go when dipped in ethanoic acid?

Answer 12

Orange

Question 13

What is a carboxylic acid?

Answer 13

A weak acid that only partially ionises in a solution

Question 14

What pH do alcohols have when dissolved in water and why?

Answer 14

A neutral pH, because they can’t gain or lose hydroxide (OH) ions

Question 15

What happens when you add sodium to alcohols?

Answer 15

Effervescence as hydrogen is being given off. This can be tested with the squeaky pop.

Question 16

What solvents are alcohols used for?

Answer 16

Medicines, perfume and cosmetics

Question 17

Why are alcohols good solvents in perfume?

Answer 17

Because they evaporate quickly from the skin

Question 18

Do alcohols burn well in air?

Answer 18

Yes they burn well in air in a combustion reaction

Question 19

What is the reaction when alcohols combust?

Answer 19

Alcohol + oxygen —-> carbon dioxide + water

Question 20

Are alcohols dangerous?

Answer 20

Ethanol is toxic in large amounts but others are even more dangerous; they can cause death in small amounts

Question 21

What are the advantages of using alcohols as fuels?

Answer 21

They’re renewable and carbon neutral

Question 22

What are two examples of alcoholic fuels?

Answer 22

Methylated spirit is used in camping stoves

Ethanol is used as car fuel

Question 23

What is the general formula for alcohols?

Answer 23

CnH2n+1OH

Question 24

What is the functional group for alcohols?

Answer 24

-OH

Question 25

What series do the different alcohols form together?

Answer 25

A homologous series

Question 26

Name the first three alcohols in order of increasing number of carbon atoms

Answer 26

Methanol Ethanol Propanol

Question 27

What do the names of all alcohols end with?

Answer 27

-ok

Question 28

What kind of compounds are alcohols?

Answer 28

Organic compounds

Question 29

Which alcohol does alcoholic drinks contain?

Answer 29

Ethanol

Question 30

What is the formula for methanol?

Answer 30

CH3OH

Question 31

What is the formula for ethanol?

Answer 31

C2H5OH

Question 32

What is the formula for propanol?

Answer 32

C3H7OH

Question 33

What colour are the simplest alcohol liquids?

Answer 33

Colourless

Question 34

What are alcohols good solvents?

Answer 34

Because they dissolve some substances that water doesn't

Question 35

What colour flames do alcohols burn with?

Answer 35

Pale blue flames