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).

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,


    Review sheet

  • 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)


    Review sheet

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