Misconceptions

1. Dissolution between solid and liquid molecules and interaction forces between them

• Specific Misconception:
  • When dissolving a solid in a liquid, there is a gap among liquid molecules therefore the liquid substance dissolves the solid substance by filling these gaps
    • http://egitimvebilim.ted.org.tr/index.php/EB/article/viewFile/546/34
      • Akgun, Abuzer. "The Relation between Science Student Teachers’ Misconceptions about Solution, Dissolution, Diffusion and their Attitudes toward Science with their Achievement." Education and Science 34.154 (2009).
• How to overcome it:
  • Explain that this is due to polarity, not states of matter
  • Explain that polar solute and polar solvent or non-polar solute and non-polar solvent dissolve better than a non-polar solvent and vice-versa
  • Dissolution of solid in liquid video:
    • http://www.youtube.com/watch?v=7PHhBBg-6X0
      • Dissolution of solid of liquid [Video file]. Retrieved from: http://www.youtube.com/watch?v=7PHhBBg-6X0

—2. Factors affecting dissolution

• Specific Misconception
  • Bonds break among molecules due to temperature only
    • http://egitimvebilim.ted.org.tr/index.php/EB/article/viewFile/546/34
      • Akgun, Abuzer. "The Relation between Science Student Teachers’ Misconceptions about Solution, Dissolution, Diffusion and their Attitudes toward Science with their Achievement." Education and Science 34.154 (2009).
• How to overcome it
  • Explain that there are other factors such as the type of solvent/solute, pressure, temperature, contact surface area, stirring
  • Perform an experiment testing these variables

—3. For a solid and liquid mixture such as sugar and water, misconceptions of water = solute and sugar = solvent because:

• Specific Misconception
  • 1.Sugar decomposes into ions
  • 2.Sugar disappears into water, water is the solute
  • 3.They both start off as solvents and then end up as solutes
    • http://ehlt.flinders.edu.au/education/iej/articles/v6n1/calik/paper.pdf
      • Çalık, Muammer, and Alipaşa Ayas. "A cross-age study on the understanding of chemical solutions and their components." International Education Journal 6.1 (2005): 30-41.
• How to overcome it
  • Sugar = solute and water = solvent because amount of solvent is greater than solute
  • Explain using the definition of a solvent; Solvent: The component of a solution that is present in the greatest amount

4. For acids and bases, misconceptions of "strong" and "weak" to be the levels of an acid or base

• Specific Misconception
  • A weak acid is not as harmful as a strong acid
  • Explain that "weak" and "strong" refer to how much the acid or base ionizes in water, and not how strong or weak it is
    • Douglass, S., Finkle, T., Gibbons, K., Searle, S., & Stewart, K. (2011). Chemistry 11 Teacher's Resource. Whitby, Canada: McGraw-Hill Ryerson Limited.

5. For acids and bases, misconceptions of "endpoint" and "equivalence point"

• Specific Misconception
  • Endpoint and equivalence point are the same
  • Review the definitions of each, and provide examples where they are the same and where they can differ
    • Douglass, S., Finkle, T., Gibbons, K., Searle, S., & Stewart, K. (2011). Chemistry 11 Teacher's Resource. Whitby, Canada: McGraw-Hill Ryerson Limited.

Next: Lesson Sequence