Freezing and phase change: How do you make ice cream?
Summary
In this lab, students will be expanding a study of phase changes. They will have had experience with exploration of the three phases of matter (plasma has been introduced but not studied.) They will be able to apply what they have learned through freezing water (liquid to a solid) and create a tasty treat for which they are familiar (ice cream.)
CollapseLearning Goals
- Apply knowledge of three phases of matter.
- Create a product using the learning about changing phases of matter.
- Work safely with a team of learners.
- Use metric measurements.
- Observing a liquid other than water, change phases.
Vocabulary: liquid, solid, freeze
- Create a product using the learning about changing phases of matter.
- Work safely with a team of learners.
- Use metric measurements.
- Observing a liquid other than water, change phases.
Vocabulary: liquid, solid, freeze
Context for Use
This lesson works well as an extension off an investigation in the FOSS intermediate kit, Chemical Interactions. Investigation 7 provides opportunity for students to explore phases changes and this provides another example for students.
Description and Teaching Materials
Introduction: At the end of Investigation 7 in Chemical Interactions after the study of phase changes.
Materials: Coffee cans (or formula cans), small freezer bags, half and half, sugar, vanilla flavoring, ice, rock salt (coarse salt), permanent marker *optional, larger freezer bags, gloves for students, camping ice cream ball
Procedure:
Discuss making homemade ice cream. Perhaps bring in the camping ice cream ball that is now so popular to show students and see if any have experience with them.
Show students the recipe. Have them convert it to metric units.
Divide students in pairs. Each student will be given a small freezer bag. Have them write their names on the outside of the bags with a permanent marker. They can measure and fill their bags from a designated station in your room. Students next close the bag and use their hands to mix the ingredients.
Next students place the two small bags in to their coffee can and place as much ice in the container as possible. Add a bit of rock salt. Students can sit across from one another on the floor. They should roll the container back and forth for approximately 20-30 minutes. I would let them roll for about 10 minutes and then check their bags. They can then add more ice and salt if needed. *If you like, you can place both small bags into a larger bag with the ice and rock salt and seal the larger bag. It is recommended students use gloves as the bag gets quite cold.
When the ice cream is complete, each student has their own bag. They can use spoons to enjoy their tasty treat!
Closure:
Have students discuss how this ice cream was made. How was it possible for the liquid to change to a solid? How was it similar to the activity done in class previous with water? How does the salt contribute to the process?
Materials: Coffee cans (or formula cans), small freezer bags, half and half, sugar, vanilla flavoring, ice, rock salt (coarse salt), permanent marker *optional, larger freezer bags, gloves for students, camping ice cream ball
Procedure:
Discuss making homemade ice cream. Perhaps bring in the camping ice cream ball that is now so popular to show students and see if any have experience with them.
Show students the recipe. Have them convert it to metric units.
Divide students in pairs. Each student will be given a small freezer bag. Have them write their names on the outside of the bags with a permanent marker. They can measure and fill their bags from a designated station in your room. Students next close the bag and use their hands to mix the ingredients.
Next students place the two small bags in to their coffee can and place as much ice in the container as possible. Add a bit of rock salt. Students can sit across from one another on the floor. They should roll the container back and forth for approximately 20-30 minutes. I would let them roll for about 10 minutes and then check their bags. They can then add more ice and salt if needed. *If you like, you can place both small bags into a larger bag with the ice and rock salt and seal the larger bag. It is recommended students use gloves as the bag gets quite cold.
When the ice cream is complete, each student has their own bag. They can use spoons to enjoy their tasty treat!
Closure:
Have students discuss how this ice cream was made. How was it possible for the liquid to change to a solid? How was it similar to the activity done in class previous with water? How does the salt contribute to the process?
Teaching Notes and Tips
This is designed to be an extension and not a stand alone lesson. It is an engaging, fun way to apply students learning of phase changes.
This is a lesson I have yet to try with my class but thought it would fit perfectly with my curriculum!
This is a lesson I have yet to try with my class but thought it would fit perfectly with my curriculum!
Assessment
If students complete the task and have edible ice cream, their work is valid. They have provide achievement of the goals.
Standards
6.1.3.4.1 Safe procedures, tools and measurement
6.1.3.4.2 Measurement using metric units
6.2.1.2.1 Physical Changes
6.2.1.2.3 Explain freezing
6.1.3.4.2 Measurement using metric units
6.2.1.2.1 Physical Changes
6.2.1.2.3 Explain freezing