AQA GCSE Combined Science: Trilogy Chemistry Paper 1 (Foundation), 2021: Question 3
12 marks · Standard Demand difficulty · Short Answer
Assess the atomic structure of carbon, the bonding in graphite, and identify different allotropes of carbon.
Practise this questionQuestion
Question text
03 Carbon can exist in a number of different structures.
03.1 What is the approximate radius of a carbon atom?
[1 mark]
Tick ( ) one box.
0.1 m 0.1 mm 0.1 nm
03.2 Figure 3 shows an atom of carbon.
Figure 3
Describe the atomic structure of this carbon atom.
You should include the number of electrons, neutrons and protons.
[6 marks]
In graphite the carbon atoms are held together by bonds.
*09* Figure 4 represents part of the structure of graphite.
Figure 4
03.3 How many bonds does each carbon atom have in graphite?
Use Figure 4.
[1 mark]
Tick ( ) one box.
12 3 4
03.4 What type of bonds hold the carbon atoms together in graphite?
[1 mark]
Tick ( ) one box.
Covalent
Ionic
Metallic 11
03.5 Lubricants allow objects to slide over each other easily.
Suggest why graphite can be used as a lubricant.
Use Figure 4.
[1 mark]
03.6 The two structures represent different forms of carbon.
Draw one line from each structure to the form of carbon.
[2 marks]
Structure Form of carbon
Buckminsterfullerene
Diamond
Graphene
Nanotube
Mark scheme
Show the mark scheme
AO /
Question Answers Extra information Mark
Spec. Ref.
03.1 0.1 nm 1 AO1
5.1.1.5
03.2 6 protons 1 AO2
8 neutrons 1 AO2
6 electrons allow electron (structure) 2,4 1 AO2
protons in nucleus 1 AO1
neutrons in nucleus 1 AO1
electrons (around nucleus) in 1 AO1
energy levels / shells
5.1.1.4
5.1.1.5
5.1.1.7
03.3 3 1 AO1
5.2.2.6
5.2.3.2
03.4 covalent 1 AO1
5.2.2.6
5.2.3.2
03.5 layers slide (over each other) allow atoms slide over each 1 AO3
other 5.2.3.2
03.6 AO1
5.2.3.1
5.2.3.3
do not accept more than one line from a box on the left
Total 12
How to answer it
Atomic Structure and Allotropes of Carbon
What this question tests
This question assesses your ability to identify the scale of atoms, describe the subatomic particles (protons, neutrons, electrons) and their locations, and link the structure of carbon allotropes (graphite, diamond, fullerenes) to their physical properties.
Atomic Scale
Correct Answer
0.1 nm
Key Knowledge
- The radius of an atom is approximately 1 × 10⁻¹⁰ m.
- 1 nanometre (nm) = 1 × 10⁻⁹ m.
- Therefore, 1 × 10⁻¹⁰ m is the same as 0.1 nm.
Describing Atomic Structure
6 Marks - Extended Response
Exam Technique: Use the Diagram!
The question asks you to describe "this" carbon atom using Figure 3. Don't just guess—count the particles shown in the image.
The 6 Marks Breakdown
- 6 protons (count the circles with '+' signs)
- 8 neutrons (count the plain black circles in the centre)
- 6 electrons (count the 'x' marks on the shells)
- Protons are in the nucleus
- Neutrons are in the nucleus
- Electrons are in shells (or energy levels)
Common Errors
- Mixing up the location of protons and electrons.
- Assuming all carbon atoms have 6 neutrons (this specific isotope has 8).
- Forgetting to mention where the particles are located.
Bonding in Graphite
Answers
03.3: 3 bonds per atom
03.4: Covalent bonds
Key Knowledge
In graphite, each carbon atom forms three strong covalent bonds. This leaves one "delocalised" electron per atom, which is why graphite conducts electricity.
Properties of Graphite
Why is it a lubricant?
The question asks you to Use Figure 4. Looking at the diagram, you can see distinct horizontal layers of atoms.
Correct Answer
The layers can slide over each other.
Common Pitfall
Students often say "it is slippery." While true, this is a property, not an explanation. To get the mark, you must mention the layers sliding.
Identifying Allotropes
Visual Identification
- Diamond: A rigid, 3D tetrahedral lattice where every carbon is bonded to 4 others. (Top image)
- Buckminsterfullerene: A hollow sphere or "soccer ball" shape (C₆₀). (Bottom image)
Matching Task
Draw one line from each structure:
- Top Structure (3D lattice) → Diamond
- Bottom Structure (Ball) → Buckminsterfullerene
Warning
Do not draw more than one line from each structure box, or you will lose the mark even if one of the lines is correct!
Topics
Chemistry · C1: Atomic Structure and the Periodic Table · C2: Bonding, Structure and the Properties of Matter
Question and mark scheme from the AQA GCSE Combined Science: Trilogy examination, Chemistry Paper 1 (Foundation), 2021. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.