AQA
Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
A-level
CHEMIST
RY
Paper 3
Friday 21 June 2024 Morning Time allowed: 2 hours
Materials
For this paper you must have: For Examiner’s Use
the Periodic Table/Data Booklet, provided as an insert (enclosed)
a ruler with millimetre measurements Question Mark
a scientific calculator, which you are expected to use where appropriate. 1
2
Instructions 3
Use black ink or black ball-point pen.
4
Fill in the boxes at the top of this page.
Answer all questions. 5
You must answer the questions in the spaces provided. Do not write outside Section B
the box around each page or on blank pages.
If you need extra space for your answer(s), use the lined pages at the end of TOTAL
this book. Write the question number against your answer(s).
All working must be shown.
Do all rough work in this book. Cross through any work you do not
want to be marked.
Information
The marks for questions are shown in brackets.
The maximum mark for this paper is 90.
Advice
You are advised to spend 70 minutes on Section A and 50 minutes on Section B.
, Answer all questions in this section.
0 1 The structure of 2-hydroxybenzenecarboxylic acid is shown.
0 1 . 1 Give the equation for the reaction of 2-hydroxybenzenecarboxylic acid with methanol.
In your equation, include the skeletal formula of the organic product.
[2 marks]
Aspirin is produced from 2-hydroxybenzenecarboxylic acid by reaction with
ethanoic anhydride in the presence of concentrated phosphoric acid.
Method
1. Add 2-hydroxybenzenecarboxylic acid to a conical flask.
2. Add excess ethanoic anhydride.
3. Add a few drops of concentrated phosphoric acid.
4. Heat the flask to 85 °C for 10 minutes.
5. Cool the flask and pour the contents into 150 cm3 of cold water.
6. Filter and wash the impure solid aspirin.
7. Recrystallise the aspirin using a 50:50 mixture of water and ethanol.
8. Check the purity of the aspirin.
0 1 . 2 Aspirin can also be produced by reacting 2-hydroxybenzenecarboxylic acid with
ethanoyl chloride.
State why ethanoic anhydride is preferred to ethanoyl chloride for this preparation.
[1 mark]
,0 1 . 3 Give the name of the mechanism for the reaction of
2-hydroxybenzenecarboxylic acid with ethanoic anhydride.
[1 mark]
0 1 . 4 Suggest the role of the concentrated phosphoric acid.
[1 mark]
0 1 . 5 Suggest why reflux is not essential when the flask is heated to 85 °C for 10 minutes.
[1 mark]
0 1 . 6 Complete and label the diagram to show how the impure solid is filtered.
[2 marks]
Question 1 continues on the next page
Turn over ►
,
Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
A-level
CHEMIST
RY
Paper 3
Friday 21 June 2024 Morning Time allowed: 2 hours
Materials
For this paper you must have: For Examiner’s Use
the Periodic Table/Data Booklet, provided as an insert (enclosed)
a ruler with millimetre measurements Question Mark
a scientific calculator, which you are expected to use where appropriate. 1
2
Instructions 3
Use black ink or black ball-point pen.
4
Fill in the boxes at the top of this page.
Answer all questions. 5
You must answer the questions in the spaces provided. Do not write outside Section B
the box around each page or on blank pages.
If you need extra space for your answer(s), use the lined pages at the end of TOTAL
this book. Write the question number against your answer(s).
All working must be shown.
Do all rough work in this book. Cross through any work you do not
want to be marked.
Information
The marks for questions are shown in brackets.
The maximum mark for this paper is 90.
Advice
You are advised to spend 70 minutes on Section A and 50 minutes on Section B.
, Answer all questions in this section.
0 1 The structure of 2-hydroxybenzenecarboxylic acid is shown.
0 1 . 1 Give the equation for the reaction of 2-hydroxybenzenecarboxylic acid with methanol.
In your equation, include the skeletal formula of the organic product.
[2 marks]
Aspirin is produced from 2-hydroxybenzenecarboxylic acid by reaction with
ethanoic anhydride in the presence of concentrated phosphoric acid.
Method
1. Add 2-hydroxybenzenecarboxylic acid to a conical flask.
2. Add excess ethanoic anhydride.
3. Add a few drops of concentrated phosphoric acid.
4. Heat the flask to 85 °C for 10 minutes.
5. Cool the flask and pour the contents into 150 cm3 of cold water.
6. Filter and wash the impure solid aspirin.
7. Recrystallise the aspirin using a 50:50 mixture of water and ethanol.
8. Check the purity of the aspirin.
0 1 . 2 Aspirin can also be produced by reacting 2-hydroxybenzenecarboxylic acid with
ethanoyl chloride.
State why ethanoic anhydride is preferred to ethanoyl chloride for this preparation.
[1 mark]
,0 1 . 3 Give the name of the mechanism for the reaction of
2-hydroxybenzenecarboxylic acid with ethanoic anhydride.
[1 mark]
0 1 . 4 Suggest the role of the concentrated phosphoric acid.
[1 mark]
0 1 . 5 Suggest why reflux is not essential when the flask is heated to 85 °C for 10 minutes.
[1 mark]
0 1 . 6 Complete and label the diagram to show how the impure solid is filtered.
[2 marks]
Question 1 continues on the next page
Turn over ►
,
