Summary

In this activity students will observe the states of matter while making a root beer float. They will also discover the differences between a solid, a liquid and a gas.

Grade Level

Elementary School

Objectives

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

• Understand what chemical and physical changes occur when ice cream is added to root beer as it relates to the states of matter.
• Identify and describe the physical properties of matter in its various states.
• Distinguish between the states of matter, and give examples of each.

Chemistry Topics

This activity supports students’ understanding of

• States of matter
• Physical Properties
• Physical change
• Chemical change

Time

Teacher Preparation: 15 minutes

Lesson: 1 hour

Materials

• Root beer (8 cups in each 2 liter bottle)
• Vanilla ice cream (1 gallon=32 scoops)
• 1 cup measuring cups, 1 per group
• Ice cream scoop, 1 per group
• Plastic cups, 1 per student
• Straws, 1 per student

Safety

• No specific safety precautions need to be observed for this activity.
• This activity is suitable for Grade levels 1-5

Teacher Notes

• This activity is suitable for Grade levels 1-5
• Depending on student’s age you may want to pre-scoop ice cream into another container.
• Brain pop Jr. has these helpful video to introduce the concepts of physical and chemical changes as well as the states of matter.
  • Video: Physical and Chemical Changes
  • Video: Changing States of Matter
• Introduce lesson: Indicate to students that they will observe 3 states of matter today. Discuss the differences of solids, liquids, and gases. Explain chemical and physical changes. Physical changes can happen when matter changes size, shape, or form. After a substance goes through a chemical change, it becomes a different substance.
• Introduce Vocabulary:
  • Physical change: matter changes size, shape, or form.
  • Chemical change: a substance becomes a different substance.
  • Physical properties: used to observe and describe matter.
  • Solid: has a definite shape and volume.
  • Liquid: has a definite volume but it takes the shape of a container.
  • Gas: fills the entire volume of a container.
• Depending on the age of the students, you may want to discuss the pre-lab questions as a class or ask students to complete them independently.
• Procedure:
  • Create an anchor chart with the students after discussing the differences in solids, liquids, and gases. (Draw a melting/evaporating ice cube and ask them to help you label each state)
  • Have students make a drawing of their cups or give them the student worksheet. Tell them they will be recording their results/labeling and adding things to the picture of the cup as we complete the activity.
  • Before you begin make sure that students remember to pour slowly because of the bubbles that will be created. Also make sure to set up paper towels for accidents-This part can get messy.
  • Have the student’s take turns measuring 1 cup of root beer and pour ½ of it into cup. Discuss what physical properties make the root beer a liquid. Have them draw and label the liquid on their picture.
  • Have students discuss what physical properties make the ice cream a solid. Then have them add two scoops of ice cream. Depending on the students age you may want to have extra help with this if possible or pre-scoop the ice cream so that they can just add it to the cup. Have them draw and label the solid on their picture.
  • Have them slowly add more root beer to the cup and observe what happens.
  • Discuss what physical properties make the foam a gas. Have them draw and label the gas on their picture.
  • What is produced? Is this a physical or chemical change? It is a chemical change, because a new substance (the gas) was formed and cannot easily be separated.
  • Students can drink their floats while they discuss the activity. Afterwards, have the students write an explanation as to what has changes occurred and why.
    • Note: Ice cream = solid; Root beer = liquid; Air bubbles = gas