AQA A-Level Chemistry Paper 1– Inorganic and Physical Chemistry Predicted Paper 2026 questions and answers
AQA
A-Level ChemistryÂ
Paper 1 – Inorganic and Physical ChemistryÂ
Predicted Paper 2026
Name ……………………………………………………………………
Date …………………
2 hours allowed
You should have access to the AQA insert (periodic table and data sheet) to help with answering the questions.
Grade boundaries
These are VERY rough guesses! Getting a C on this paper does not guarantee you the same mark in the exam.
• A* - 90
• A – 80
• B – 70
• C – 60
• D – 50
• E - 40
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01 The Born Haber cycle below can be used to determine the lattice enthalpy of NaCl. The cycle includes the value for the enthalpy changes of the steps labelled A-F.
01.1 Complete the Born-Haber cycle by adding the species present on the two dotted lines. Include state symbols.
[2 marks]
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Energy change Letter
Enthalpy change of atomization of chlorine A
Lattice energy of sodium chloride E
First electron affinity of chlorine F
01.2 Name the enthalpy changes for the following steps in the Born-Haber cycle.
[3 marks]
B:Â
C:Â
D:Â
01.3 Calculate the lattice enthalpy of NaCl.
[1 mark]
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02 The table below gives the relative abundance of each isotope in the mass spectrum of element X.
Mass number of isotope Percentage abundance
54 6.10
56 92.0
57 1.90
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02.1
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i. Calculate the relative atomic mass of the element X. Give your answer to three significant figures.
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[2 marks]
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ii. Identify the element X.
[1 mark]
02.2 The isotopes are converted into ions in a spectrometer. They are separated by deflection and then detected.
Describe how ions are formed and detected in a time of flight (TOF) mass spectrometer.
[4 marks]
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02.3 In a TOF mass spectrometer the kinetic energy (KE) of a 56 Fe 2+ ion was 1.562×10-13 J. Calculate the velocity of the ion using the below equation.
KE = ½ mv2
(m= mass/kg and v= velocity/ms-1) (Avogadro constant L= 6.022×1023 mol-1)
[3 marks]
Velocity = ms-1
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03
03.1 What is meant by the term ‘buffer solution’?
[2 marks]
03.2 A phosphate buffer system contains both Na2HPO4 and NaH2PO4. The following equilibrium is present in the solution.
H2PO4- + H2O ⇌ HPO42- + H3O+
i. Explain how a solution containing a mixture of H2PO4- and HPO42- acts as a buffer.
[2 marks]
ii. Write an expression for the Ka of H2PO4-.
[1 mark]
iii. 100 cm3 of 0.5 moldm-3 Na2HPO4 and 100 cm3 of 0.3 moldm-3 NaH2PO4 are needed to give a pH of 7.43 in the phosphate buffer system.
Calculate the value of Ka.