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Categorizing States of Matter Mark as Favorite (96 Favorites)

ACTIVITY in Physical Properties, Molecular Motion. Last updated March 25, 2020.


In this activity students will analyze both written statements and images that describe the properties of a solid, liquid or gas. Students will determine which state of matter the description best describes and categorize it accordingly.

Grade Level

High and Middle School

NGSS Alignment

This activity will help prepare your students to meet the performance expectations in the following standards:

  • MS-PS1-4: Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.
  • Scientific and Engineering Practices:
    • Engaging in Argument from Evidence


By the end of this activity, students should be able to

  • Distinguish between the states of matter at the particle level.
  • Explain, using examples how matter is different in one state versus another.
  • Identify examples of different states of matter.

Chemistry Topics

This lesson supports students’ understanding of

  • States of Matter
  • Molecular Motion
  • Physical Properties


Teacher Preparation: 5-10 minutes

Lesson: 30 minutes


  • Printed copies of student handout
  • scissors


  • There are no safety considerations for this activity.

Teacher Notes

  • Students should work in pairs for this categorization activity.
  • Teachers could pre-cut the descriptions and images, and use them for more than one class/save to use each year.
  • Students should be encouraged to discuss their categorization methods, and share with the class. Students should justify their choices, and discuss any selections that they are unsure of.
  • Images used in this activity are from WikiMediaCommons.
    • Ice cubes: By Darren Hester (Openphoto.net)
    • Match: By Sebastian Ritter
    • Toothpaste: By Scott Ehardt
    • Beaker of liquid particles: By Dale J. Brug
    • Solid Particles: By Niabot
    • *Other images do not require attribution.
  • For more information about this activity and for ideas about similar activities, read the associated article in the May 2018 issue of Chemistry Solutions.

For the Student



Cut-out the following statements and pictures below and, with the help of your partner, categorize them into the states they best associated with (solid, liquid or gas) on the next page.

We can’t feel it The particles move quickly The particles have some movement energy It has a fixed volume, but it does not have a fixed shape.
It fills any container you put it in The particles move very slowly It spreads out in all directions It does not have a fixed volume or a fixed shape
It flows from one container to another The particles are spaced far apart The particles have almost no movement energy The particles are spaced very close together
It has a fixed size and shape The particles are spaced somewhat close together It keeps its own shape and size It feels “runny”
It spreads to fill the bottom of a container. It often feels “hard” It can’t really be squeezed, but is easy to feel It can be squeezed, but it feels wet
It can be squeezed A LOT, but we have trouble feeling it