Many students struggle to explain the constancy of temperature during a change of state despite continuous heating or cooling
Resources to Address This
Examination of boiling (11-16)
This activity follows the heating of a liquid until it boils and introduces latent heat.
- Bubbles cannot form and grow in the liquid until the vapour pressure in them matches the outside atmospheric pressure. The liquid boils away as fast as heating provides the 'exit-taxi' of latent heat. Once the liquid is boiling, further heating simply equips more molecules with the speed needed to evaporate into vapour bubbles. Therefore, the temperature stays constant at the boiling point.
- Jasien, P. G. () Roles of Terminology, Experience and Energy Concepts in Student Conceptions of Freezing and Boiling, Journal of Chemical Education, 90, 1609-1615.
Researchers analyse student conceptions of solid-liquid and liquid-vapour phase transitions using data from 117 undergraduate chemistry students, using data from open-ended, short-answer questions. The collected responses offer insights into students' understanding of these phase changes.
- Chu, H, Treagust, D. F., Yeo, S. and Zadnik, M. () Evaluation of Students' Understanding of Thermal Concepts in Everyday Contexts, International Journal of Science Education, 34, (10), 1509-1534.
This research finds a wide range of misconceptions about temperature and energy held by secondary school students, revealing that the students can have a very confused understanding of thermal physics and how energy is transferred by thermal processes such as conduction and radiation. To tackle these ideas students need to be taught clear links between energy transfer and heating, based on the initial idea of transfer of energy from ‘hot’ to ‘cold’ materials, and moving towards the idea of thermal equilibrium.