Some students think that during evaporation mass is lost

Properties of Matter


Students may think that during chemical reactions (and some phase transitions) a substance 'disappears' (e.g petrol used up in a combustion engine disappears or spilt water disappears, rather than evaporating).

Alternatively, some students will intuitively apply a principle of conservation of 'matter', but not appreciate that this implies conservation of 'weight'. For example, students may think that water molecules in the gas state are lighter than they are in the solid state.

Diagnostic Resources

The following worksheets may help to identify whether students hold this particular misconception.

For more information, see the University of York BEST website.


  • Andersson, B., () Pupils' Conceptions of Matter and its Transformations (age 12-16), Studies in Science Education, 18, 53-85.

    This research shows that some of the misconceptions students have about matter are reinforced by the learning materials and approaches used in classrooms. Textbook illustrations can give false impressions about sizes, scales and movement and the limitations of models can give misleading ideas. This paper explains why teachers need to be aware of the misconceptions that can be produced and how to tackle some of them.

    Paper digest

  • Aydeniz, M. and Kotowski, E. L., () What do Middle and High School Students Know About the Particulate Nature of Matter After Instruction? Implications for Practice. School Science and Mathematics, 112 (2) 59-65.

Limit Less Campaign

Support our manifesto for change

The IOP wants to support young people to fulfil their potential by doing physics. Please sign the manifesto today so that we can show our politicians there is widespread support for improving equity and inclusion across the education sector.

Sign today