Boz (2006)

This Turkish study probed 300 students’ (aged 12-18) conceptions of the particle nature of matter, identifying some misconceptions. It shows that students are reluctant to explain phase changes in terms of particle behaviour and instead tend to describe macroscopic changes.

Learners’ ideas

  • Many pupils believed particles in a solid state to have no movement at all.
  • Many younger pupils attributed macroscopic behaviours to microscopic particles (e.g. "ice particles melted").
  • Some younger pupils associated the particles with small units of the substance rather than something related to chemical composition.
  • Younger students often struggle to explain the difference between particles of the same phase at varying temperatures, either claiming there's no difference or stating it's "hotter."
  • Many pupils explained phase change behaviour in terms of macroscopic properties of substances, not particulate properties.
  • Some younger pupils believed there to be no intermolecular forces in liquids because they could flow.
  • Some younger students thought that melting and boiling points changed in environments at different temperatures.


  • Teachers should help students link the particulate theory with phase changes by asking them to use the particulate nature of matter in describing phase changes.
  • Teachers should distinguish between the everyday usage of words and the scientist's usage.
  • Computer simulation representing the temperature rise and the change in the arrangement of particles might be helpful to allow students to understand changes of state.
  • The distinction between the macroscopic and microscopic world should be made clear to the students.

Study Structure


  1. What knowledge do Turkish students have about the way in which particles behave in solids, liquids and gases?
  2. Can Turkish students apply ideas about the particulate nature of matter to explain phase changes?
  3. Is there a significant difference in understanding the particulate nature of matter between the age groups?

Evidence collection

Participants completed a 6-item open-ended questionnaire followed up by semi-structured interviews which were recorded and transcribed. Some questions were adapted from prior studies and others were developed by the researchers based on analysis of textbooks.

Question responses were analysed quantitatively and coded into correct, partially correct and incorrect. Simple statistical methods were then applied to the proportions of responses in each category.

Details of the sample

The sample consisted of 300 Turkish students as follows:

  • 40 in year 6 (12-13 years old)
  • 60 in year 8 (14-15 years old)
  • 200 in year 11 (17-18 years old)
  • 141 were female and 159 were male.
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