Atomic Structure | AQA A-Level Chemistry (7405)
Atomic Structure
- 89 questions
- 7 subtopics
- Physical chemistry, drawn on by Paper 1 and Paper 2
- Paper 1, Paper 2 and Paper 3
Atomic structure is the first topic and is examined on Papers 1 and 3.
It sets up the particles an atom is built from, how mass spectrometry weighs them, how electrons arrange themselves into sub-shells, and how ionisation energies give away that arrangement.
Sample questions from Atomic Structure
Answer each one closed book first, then open the answer.
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Fundamental Particles
What is the relative mass of a proton?
Show the answer
1 -
Fundamental Particles
Where in an atom are neutrons located?
Show the answer
In the nucleus -
Mass Number and Isotopes
How do you determine the number of electrons in a neutral atom?
Show the answer
The number of electrons equals the atomic number (same as the number of protons). -
Mass Number and Isotopes
Why do isotopes of the same element have different physical properties?
Show the answer
They have different masses due to different numbers of neutrons. -
Time of Flight Mass Spectrometry: Ionisation and Acceleration
What is electron impact ionisation?
Show the answer
A technique where high-energy electrons are fired at the sample, knocking off an electron to form a positive ion -
Time of Flight Mass Spectrometry: Ionisation and Acceleration
How are ions accelerated in a TOF mass spectrometer?
Show the answer
By passing them through an electric field created by charged plates -
Time of Flight Mass Spectrometry: Drift, Detection and Calculating m/z
How is the time of flight related to the mass to charge ratio of an ion?
Show the answer
Ions with smaller m/z ratios have shorter flight times; ions with larger m/z ratios have longer flight times -
Time of Flight Mass Spectrometry: Drift, Detection and Calculating m/z
How can the m/z ratio be calculated from the time of flight, distance travelled and kinetic energy?
Show the answer
m/z = 2KE × t²/d² (derived by combining v = d/t with v = √(2KE/m))
The 7 subtopics
One subtopic is one session. Work down the list.
| Subtopic | What it covers | Questions |
|---|---|---|
| Fundamental Particles | Protons, neutrons and electrons, and the relative mass and charge of each. | 13 |
| Mass Number and Isotopes | Mass number, atomic number, and how isotopes of the same element differ. | 12 |
| Time of Flight Mass Spectrometry: Ionisation and Acceleration | The first two stages of the instrument: electrospray and electron impact ionisation, and acceleration to constant kinetic energy. | 12 |
| Time of Flight Mass Spectrometry: Drift, Detection and Calculating m/z | Why heavier ions drift more slowly, what happens at the detector, and getting relative atomic mass from the spectrum. | 10 |
| Electron Configuration: Sub-shells and Orbitals | The s, p, d and f sub-shells, how many electrons each holds, and the order they fill in. | 12 |
| Electron Configuration: Writing Configurations for Atoms and Ions | Writing configurations out for atoms and ions, including the chromium and copper exceptions. | 11 |
| Ionisation Energies and Periodic Trends | Defining first and successive ionisation energies, and reading trends across periods and down groups. | 19 |
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Nearby topics
AQA A-Level Chemistry Active Recall Guide
Every topic, not just this one. 2,442 questions with their answers.