Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

A-Level OCR Chemistry > 14. Alcohols > Flashcards

14. Alcohols Flashcards

1
Q

What is the functional group of alcohol?

A

CnH2n+1OH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Is alcohol saturated or unsaturated?

A

Saturated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Is alcohol polar or non-polar? Why?

A

Non-polar, because:
1. the difference in electronegativity of hydrogen and oxygen is big
2. there are weak London forces but there are stronger hydrogen bonds between the polar O—H groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Is alcohol water soluble? Why?

A

Soluble, because:
1. hydrogen bonds form between the polar —OH group of alcohol and water
2. as the hydrocarbon chain increases, the influence of —OH group becomes smaller

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How is alcohol’s volatility compared to the corresponding alkane?

A

Alcohols are less volatile, because:
1. hydrogen bonds hold the alcohol molecule together
2. in order to turn liquid alcohol into gas, hydrogen bonds must be broken
3. it requires more energy to break hydrogen bonds than London forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How is alcohol’s boiling point compared to the corresponding alkane?

A

Alcohol has a higher boiling point, because:
1. hydrogen bonds hold the alcohol molecule together
2. in order to turn liquid alcohol into gas, hydrogen bonds must be broken
3. it requires more energy to break hydrogen bonds than London forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How do primary alcohols look like?

A

The —OH group is attached to a carbon atom that is attached to two hydrogen atoms and one alkyl group.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do secondary alcohols look like?

A

The —OH group is attached to a carbon atom that is attached to one hydrogen atom and two alkyl groups.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How do tertiary alcohols look like?

A

The —OH group is attached to a carbon atom that is attached to no hydrogen atom and three alkyl groups.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the equation of complete combustion of alcohol?

A

Alcohol + oxygen > carbon dioxide + water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the equation of incomplete combustion of alcohol?

A

Alcohol + oxygen > carbon monoxide + water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which types of alcohol can be oxidised?

A

Primary and secondary alcohol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the main types of oxidising agents?

A
  1. potassium/sodium dichromate (VI)
    ↳ K2Cr2O7
    ↳ Na2Cr2O7
  2. potassium manganate (VII)
    ↳ KMnO4
    WITH dilute sulphuric acid
    ↳ H2SO4
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is used to represent oxidising agents?

A

[O]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What happens to the oxidising agent when it reacts with an organic molecule?

A

It is reduced, often resulting in a colour change.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the colour change of dichromate (VI) ions when reacting with alcohol?

A

Orange > green

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What will the number of dichromate (VI) ions change?

A

Cr2O7 2- > Cr 3+

18
Q

What is the colour change of potassium manganate (VII) when reacting with alcohol?

A

Purple > colourless

19
Q

What is the colour change of dilute sulphuric acid when reacting with alcohol?

A

No change in colour

20
Q

What is the product of incomplete oxidation of primary alcohol?

A

Aldehyde + water

21
Q

What is the functional group of aldehyde? How to name aldehyde?

A

C=O. Remove the -e and add -al, eg. propanal.

22
Q

What condition is required to produce aldehyde when oxidising primary alcohol?

A
  1. when distillation is used
  2. when the alcohol is in excess
23
Q

What is the product of complete oxidation of primary alcohol?

A

Carboxylic acid + water

24
Q

What is the functional group of carboxylic acid? How to name carboxylic acid?

A

COOH. Remove the -e and add -oic acid, eg. propanoic acid.

25
Q

What condition is required to produce carboxylic acid when oxidising primary alcohol?

A
  1. when reflux is used
  2. when the oxidising agent is in excess
26
Q

Can aldehyde be further oxidised? How?

A

Yes. Aldehyde can be further oxidised to form carboxylic acid when reflux and oxidising agent are used.

27
Q

What is the product of oxidation of secondary alcohol?

A

Ketone + water

28
Q

What is the functional group of ketone? How to name ketone?

A

C=O. Remove the -e and add -one, eg. propanone.

29
Q

What condition is required to produce ketone when oxidising secondary alcohol?

A

When reflux is used

30
Q

Can ketone be further oxidised?

A

No

31
Q

What is the difference between aldehyde and ketone?

A

Aldehyde: C is bonded with O, H, R
Ketone: C is bonded with O, R, R

32
Q

Can tertiary alcohol be oxidised? Why?

A

No, because the central carbon atom is already bonded to three other carbon atoms.

33
Q

What is an example of elimination of alcohol?

A

Dehydration

34
Q

What happens during dehydration?

A

A water molecule is removed

35
Q

What is the product of dehydration?

A

Alkene + water

36
Q

What condition is required to start dehydration?

A
  1. heat under reflux
  2. acid catalyst, eg. H2SO4
37
Q

What is the product when alcohol reacts with hydrogen halides?

A

Haloalkanes + water

38
Q

What condition is required to start substitution?

A

Acids, eg. H2SO4

39
Q

How is aqueous hydrogen halide produced?

A

Refluxing alcohol with sodium halide (eg. NaBr) and sulfuric acid.

40
Q

Why do we reflux the alcohol with sodium halide and sulfuric acid?

A

Because hydrogen halides are gases at room temperature, which are unsafe to use.

A-Level OCR Chemistry (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions