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A-level
CHEMIST
RY
Paper 3
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 Section B
write outside the box around each page or on blank pages.
TOTAL
If you need extra space for your answer(s), use the lined pages at
the end of 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.
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outside the
Section A box
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]
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0 1 . 3 Give the name of the mechanism for the reaction of box
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
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