AQA AS Chemistry Paper 1: Inorganic &
Physical Chemistry | 2025/2026
Complete Exam Prep – Pass on First
Attempt
**1. Describe the nuclear model of an atom.** [2 marks]
A) Nucleus containing protons and electrons, surrounded by neutrons in energy levels.
B) Nucleus containing protons and neutrons, surrounded by electrons in energy levels.
C) Nucleus containing neutrons and electrons, surrounded by protons in energy levels.
D) A solid sphere with no internal structure.
💫ANSWER✔️✔️: B
💫RATIONALE✔️✔️: The nuclear model describes the atom as having a central nucleus containing
protons and neutrons, with electrons orbiting in energy levels. This model was developed from
Rutherford's gold foil experiment and is fundamental to understanding atomic structure for AQA AS
Chemistry exam success .
**2. State the relative mass and charge of a proton.** [2 marks]
A) Mass: 1, Charge: 0
B) Mass: 1, Charge: +1
C) Mass: 1/1840, Charge: -1
,D) Mass: 1, Charge: -1
💫ANSWER✔️✔️: B
💫RATIONALE✔️✔️: A proton has a relative mass of 1 and a relative charge of +1. This is essential
knowledge for AQA AS Chemistry Paper 1, covering atomic structure and subatomic particles .
**3. Define the term 'isotope'.** [1 mark]
A) Atoms with the same number of neutrons but a different number of protons.
B) Atoms with the same number of protons but a different number of neutrons.
C) Atoms with the same number of protons and neutrons.
D) Atoms with different numbers of protons and electrons.
💫ANSWER✔️✔️: B
💫RATIONALE✔️✔️: Isotopes are atoms of the same element with the same number of protons but
different numbers of neutrons. This definition is key to understanding mass spectrometry and relative
atomic mass calculations in AQA AS Chemistry revision .
**4. Give the full electron configuration of an aluminium (Al) atom.** [1 mark]
A) 1s² 2s² 2p⁶ 3s² 3p¹
B) 1s² 2s² 2p⁶ 3s² 3p²
C) 1s² 2s² 2p⁶ 3s¹ 3p²
D) 1s² 2s² 2p⁶ 3s² 3p⁶
💫ANSWER✔️✔️: A
💫RATIONALE✔️✔️: Aluminium has atomic number 13, giving the configuration 1s² 2s² 2p⁶ 3s² 3p¹.
This is a core topic in AQA AS Chemistry Paper 1 Inorganic and Physical Chemistry exam questions .
, **5. Deduce the formula of the ion that has a charge of 2+ and the same electron configuration as
argon.** [1 mark]
A) Ca²⁺
B) Sr²⁺
C) Mg²⁺
D) Ba²⁺
💫ANSWER✔️✔️: B
💫RATIONALE✔️✔️: Strontium (Sr) forms a 2+ ion with the electron configuration of argon (1s² 2s²
2p⁶ 3s² 3p⁶). This tests understanding of electron configurations and ion formation for AQA AS
Chemistry exam practice .
**6. Deduce which of Na⁺ and Mg²⁺ is the smaller ion. Give a reason.** [2 marks]
A) Na⁺ is smaller because it has fewer protons.
B) Mg²⁺ is smaller because it has more protons and the same shielding.
C) Na⁺ is smaller because it has more shielding.
D) Mg²⁺ is smaller because it has fewer electron shells.
💫ANSWER✔️✔️: B
💫RATIONALE✔️✔️: Mg²⁺ is smaller than Na⁺. Both have the same electron configuration and
shielding, but Mg²⁺ has more protons, creating a higher nuclear charge and stronger attraction to the
outer electrons, reducing the ionic radius. This is a key concept in periodicity for AQA AS Chemistry
revision notes .
**7. Write the equation for the first ionisation of sodium.** [1 mark]
A) Na(g) → Na⁺(g) + e⁻
B) Na(s) → Na⁺(g) + e⁻
C) Na(g) + e⁻ → Na⁻(g)
Physical Chemistry | 2025/2026
Complete Exam Prep – Pass on First
Attempt
**1. Describe the nuclear model of an atom.** [2 marks]
A) Nucleus containing protons and electrons, surrounded by neutrons in energy levels.
B) Nucleus containing protons and neutrons, surrounded by electrons in energy levels.
C) Nucleus containing neutrons and electrons, surrounded by protons in energy levels.
D) A solid sphere with no internal structure.
💫ANSWER✔️✔️: B
💫RATIONALE✔️✔️: The nuclear model describes the atom as having a central nucleus containing
protons and neutrons, with electrons orbiting in energy levels. This model was developed from
Rutherford's gold foil experiment and is fundamental to understanding atomic structure for AQA AS
Chemistry exam success .
**2. State the relative mass and charge of a proton.** [2 marks]
A) Mass: 1, Charge: 0
B) Mass: 1, Charge: +1
C) Mass: 1/1840, Charge: -1
,D) Mass: 1, Charge: -1
💫ANSWER✔️✔️: B
💫RATIONALE✔️✔️: A proton has a relative mass of 1 and a relative charge of +1. This is essential
knowledge for AQA AS Chemistry Paper 1, covering atomic structure and subatomic particles .
**3. Define the term 'isotope'.** [1 mark]
A) Atoms with the same number of neutrons but a different number of protons.
B) Atoms with the same number of protons but a different number of neutrons.
C) Atoms with the same number of protons and neutrons.
D) Atoms with different numbers of protons and electrons.
💫ANSWER✔️✔️: B
💫RATIONALE✔️✔️: Isotopes are atoms of the same element with the same number of protons but
different numbers of neutrons. This definition is key to understanding mass spectrometry and relative
atomic mass calculations in AQA AS Chemistry revision .
**4. Give the full electron configuration of an aluminium (Al) atom.** [1 mark]
A) 1s² 2s² 2p⁶ 3s² 3p¹
B) 1s² 2s² 2p⁶ 3s² 3p²
C) 1s² 2s² 2p⁶ 3s¹ 3p²
D) 1s² 2s² 2p⁶ 3s² 3p⁶
💫ANSWER✔️✔️: A
💫RATIONALE✔️✔️: Aluminium has atomic number 13, giving the configuration 1s² 2s² 2p⁶ 3s² 3p¹.
This is a core topic in AQA AS Chemistry Paper 1 Inorganic and Physical Chemistry exam questions .
, **5. Deduce the formula of the ion that has a charge of 2+ and the same electron configuration as
argon.** [1 mark]
A) Ca²⁺
B) Sr²⁺
C) Mg²⁺
D) Ba²⁺
💫ANSWER✔️✔️: B
💫RATIONALE✔️✔️: Strontium (Sr) forms a 2+ ion with the electron configuration of argon (1s² 2s²
2p⁶ 3s² 3p⁶). This tests understanding of electron configurations and ion formation for AQA AS
Chemistry exam practice .
**6. Deduce which of Na⁺ and Mg²⁺ is the smaller ion. Give a reason.** [2 marks]
A) Na⁺ is smaller because it has fewer protons.
B) Mg²⁺ is smaller because it has more protons and the same shielding.
C) Na⁺ is smaller because it has more shielding.
D) Mg²⁺ is smaller because it has fewer electron shells.
💫ANSWER✔️✔️: B
💫RATIONALE✔️✔️: Mg²⁺ is smaller than Na⁺. Both have the same electron configuration and
shielding, but Mg²⁺ has more protons, creating a higher nuclear charge and stronger attraction to the
outer electrons, reducing the ionic radius. This is a key concept in periodicity for AQA AS Chemistry
revision notes .
**7. Write the equation for the first ionisation of sodium.** [1 mark]
A) Na(g) → Na⁺(g) + e⁻
B) Na(s) → Na⁺(g) + e⁻
C) Na(g) + e⁻ → Na⁻(g)
