Formative Assessment
Formative Assessment icon

Can students envision what might happen at the microscopic level to explain why air is more compressible than water?

Annotated student notebook page

Magnifier icon Enlarge Notebook Sample

Look for evidence of students  explanations in their annotated notebook entries on the page Explaining the difference in compressibility of water and air.

As you interpret student work, remember, students have not yet viewed air with the Particle Magnifier. They are basing their ideas on first–hand experience compressing air and water and using the Particle Magnifier to explore particles of water and ice.

Does the drawing show that:

  • Air is more compressible than water.
  • Both water and air are made of particles.
  • There is more space between air particles so they can be pushed closer together.

A next step might be to ask students if they think ice would be compressible or not.