Describe the limitations of the particle model when used to explain the behaviour of substances.

Eduqas GCSE Chemistry — 2.1 Bonding, structure and properties · Describe · 4 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

The particle model represents particles as small, solid spheres and is used to explain the three states of matter and changes of state.

Model answer (4 marks)

1. The model does not show the forces that act between particles, so it cannot explain attraction or repulsion.
2. All particles are drawn as spheres, yet real atoms, molecules and ions are not perfectly spherical.
3. The spheres are depicted as solid objects, whereas real particles are not solid but have internal structure.
4. The model cannot explain why atoms of certain elements react with each other, i.e. the chemical reactivity of elements.

Examiner tips

Use the exact wording from the mark scheme, e.g. "does not show the forces between particles". Include all four points in separate sentences. Keep the answer concise – no extra explanation beyond the four points.

Common mistakes

Writing the points in a different order or omitting one. Using vague phrases such as "doesn't show interactions" instead of the exact wording. Adding unnecessary details or explanations that are not asked for.

Mark scheme (4 marks)

The particle model does not show forces between particles
All particles are represented as spheres, but real particles are not spherical
The spheres are shown as solid, but real particles are not solid objects
The particle model does not explain why atoms of some elements react with one another

Key terms in this question

particle model

More Bonding, structure and properties questions

▶ Try answering this question with AI marking (free) →