AQA_2024: A-level Chemistry - Paper 3
(Merged Question Paper and Marking Scheme)
Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signat ure
I declare this is my own work.
A-level
CHEMISTRY
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.
Fill in the boxes at the top of this page. 4
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.
IB/M/Jun24/G4006/E8 7405/3
,For A-level Chemistry Paper 3, which typically focuses on Practical Skills and Planning, Analysis, and
Evaluation, concentrate on the following key areas:
1. Practical Skills:
Experimental Techniques: Be familiar with a range of practical techniques, such as titrations,
distillation, filtration, separations, and identifying compounds. Ensure you can explain the purpose
and procedure for each.
Quantitative Analysis: Understand how to calculate concentrations, molarities, and volumes, especially in
acid-base titrations. Be able to perform calculations involving moles and stoichiometry from experimental
data.
Reaction Rates: Know how to measure the rate of reaction experimentally and calculate rate constants.
Understand how to interpret rate laws and the effect of concentration and temperature on reaction rate.
Using Equipment: Be confident in using common lab equipment, such as burettes, pipettes, volumetric
flasks, and calorimeters, and know how to minimize sources of error.
Safety Protocols: Understand laboratory safety and how to handle chemicals and equipment safely during
experiments.
2. Planning and Methodology:
Designing Experiments: Be able to plan experiments based on given problems, identifying key variables
(independent, dependent, control), selecting appropriate equipment, and detailing the procedure. Include
ideas for reproducibility, accuracy, and precision in experiments.
Control of Variables: Understand how to control variables to ensure fair tests and obtain reliable results.
This includes controlling temperature, concentration, pressure, etc.
Error Considerations: Know how to identify potential sources of error (e.g., systematic errors, random
errors) and propose ways to minimize or account for them (e.g., repeated trials, using more accurate
instruments).
3. Data Analysis:
Graphical Analysis: Be able to plot and interpret data, especially for reaction kinetics, equilibrium
concentrations, and titration results. Understand how to analyze trends and use graphs for extrapolation
and interpolation.
Statistical Analysis: Know how to calculate uncertainties in measurements and determine the percentage
uncertainty. Be familiar with significant figures and how they affect calculations and results.
Calculations: Practice calculations involving moles, concentrations, yield, and reaction enthalpies from
experimental data. Make sure you are comfortable with conversions and units.
4. Evaluation and Conclusion:
Interpretation of Results: Be able to evaluate experimental data, assess its reliability, and identify trends
or inconsistencies. Draw conclusions based on evidence.
Evaluation of Experimental Design: Critically assess the design and methodology of an experiment,
considering factors such as accuracy, precision, and limitations.
Suggest Improvements: Be prepared to suggest ways to improve the experiment, such as using more
precise equipment, increasing the number of trials, or considering alternative methods.
6. Exam Technique:
Clear and Concise Responses: For planning questions, write clear and concise steps, specifying the aim,
method, apparatus, and expected results. Ensure any calculations are shown step-by-step.
Show Understanding: When discussing the evaluation or improvements to experiments, demonstrate
understanding of validity, reliability, and control of variables.
Time Management: Manage your time to ensure you address both the practical and theoretical aspects of
the questions effectively.
IB/M/Jun24/G4006/E8 7405/3
, 2
Do not write
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]
IB/M/Jun24/7405/3
, 3
Do not write
outside the
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
Turn over ►
IB/M/Jun24/7405/3
(Merged Question Paper and Marking Scheme)
Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signat ure
I declare this is my own work.
A-level
CHEMISTRY
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.
Fill in the boxes at the top of this page. 4
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.
IB/M/Jun24/G4006/E8 7405/3
,For A-level Chemistry Paper 3, which typically focuses on Practical Skills and Planning, Analysis, and
Evaluation, concentrate on the following key areas:
1. Practical Skills:
Experimental Techniques: Be familiar with a range of practical techniques, such as titrations,
distillation, filtration, separations, and identifying compounds. Ensure you can explain the purpose
and procedure for each.
Quantitative Analysis: Understand how to calculate concentrations, molarities, and volumes, especially in
acid-base titrations. Be able to perform calculations involving moles and stoichiometry from experimental
data.
Reaction Rates: Know how to measure the rate of reaction experimentally and calculate rate constants.
Understand how to interpret rate laws and the effect of concentration and temperature on reaction rate.
Using Equipment: Be confident in using common lab equipment, such as burettes, pipettes, volumetric
flasks, and calorimeters, and know how to minimize sources of error.
Safety Protocols: Understand laboratory safety and how to handle chemicals and equipment safely during
experiments.
2. Planning and Methodology:
Designing Experiments: Be able to plan experiments based on given problems, identifying key variables
(independent, dependent, control), selecting appropriate equipment, and detailing the procedure. Include
ideas for reproducibility, accuracy, and precision in experiments.
Control of Variables: Understand how to control variables to ensure fair tests and obtain reliable results.
This includes controlling temperature, concentration, pressure, etc.
Error Considerations: Know how to identify potential sources of error (e.g., systematic errors, random
errors) and propose ways to minimize or account for them (e.g., repeated trials, using more accurate
instruments).
3. Data Analysis:
Graphical Analysis: Be able to plot and interpret data, especially for reaction kinetics, equilibrium
concentrations, and titration results. Understand how to analyze trends and use graphs for extrapolation
and interpolation.
Statistical Analysis: Know how to calculate uncertainties in measurements and determine the percentage
uncertainty. Be familiar with significant figures and how they affect calculations and results.
Calculations: Practice calculations involving moles, concentrations, yield, and reaction enthalpies from
experimental data. Make sure you are comfortable with conversions and units.
4. Evaluation and Conclusion:
Interpretation of Results: Be able to evaluate experimental data, assess its reliability, and identify trends
or inconsistencies. Draw conclusions based on evidence.
Evaluation of Experimental Design: Critically assess the design and methodology of an experiment,
considering factors such as accuracy, precision, and limitations.
Suggest Improvements: Be prepared to suggest ways to improve the experiment, such as using more
precise equipment, increasing the number of trials, or considering alternative methods.
6. Exam Technique:
Clear and Concise Responses: For planning questions, write clear and concise steps, specifying the aim,
method, apparatus, and expected results. Ensure any calculations are shown step-by-step.
Show Understanding: When discussing the evaluation or improvements to experiments, demonstrate
understanding of validity, reliability, and control of variables.
Time Management: Manage your time to ensure you address both the practical and theoretical aspects of
the questions effectively.
IB/M/Jun24/G4006/E8 7405/3
, 2
Do not write
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]
IB/M/Jun24/7405/3
, 3
Do not write
outside the
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
Turn over ►
IB/M/Jun24/7405/3
