Liquids and Solids

Liquids and Solids

Target Grade Level / Age Range:

Kindergarten – 2nd grade

Time:

1 hour

Purpose/Objective:

Students will explore, through hands-on experiments, the concepts of liquid and solid.

Materials: 

  • Life on a Dairy Farm by Judy Wolfman
  • Butter
    • Heavy Whipping Cream
    • Pinch of table salt
    • Small plastic container with tight sealing lid (New Urine specimen cups work great.  They are sterile and no need to worry about breaking if dropped)
    • Colander
    • Loaf of Bread or crackers
    • Butter Knife
    • Napkin
  • Ice Cream
    • 2 cartons of ice cream mix (Available where soft serve ice cream is sold)
    • Quart size freezer zip lock bag
    • Gallon size freezer zip lock bag
    • Ice cream salt (Rock salt)
    • Crushed ice
    • Scissors, bowls, and spoons
  • Oobleck
    • 1 package of corn starch
    • Untreated dent corn kernels
    • Pitcher of water
    • Tablespoon measure
    • Paper plate
    • Spoon

Suggested Companion Resources:

  • The Milk Makers by Gail Gibbons
  • Ice Cream the Full Scoop by Gail Gibbons
  • Milk to Ice Cream How Things are Made by Inez Synder
  • Let’s Make Butter by Christian and Eleanor
  • Winter Days in the Big Woods by Laura Ingalls Wilder
  • Making Butter written by Jenny Feely and illustrated by Marjory Gardner GRL:C
  • Making Ice Cream by Ted Cortese GRL: D

Vocabulary:

  • Liquid – A liquid is something that changes its shape when it is moved from one container to another, but has a constant volume.
  • Solid - A solid stays the same shape when it is moved from one container to another, but has a constant volume.

Interest Approach or Motivator: 

As a class, discuss the states of matter. Have students give examples of solids, liquids, and gasses. Bring up the classic example of water, which can exist as all three. Ask students if they can think of any common food items that exist in both a solid and liquid form. One example of this would be milk, which can be made into ice cream through a change in temperature and butter through agitation (stirring) which causes fat molecules to clump together and create a solid.

Background – Agricultural Connections:

Corn and milk are both agriculture products that are very important to everyday life. Both products start on the farm.

Milk comes from dairy cows, which are raised on dairy farms. In order to produce milk, a dairy cow must first have a calf, or a baby cow. A dairy cow may have over 10 calves in her lifetime! Then she begins to produce milk. Dairy cows are milked 2-3 times per day on most farms. Milking does not hurt the cows; in fact, most cows enjoy being milked.

Once milk has been collected from the cow, it is transported to a bulk tank, where it is cooled and stored until a refrigerated milk truck comes to transport it to a plant. There, it is pasteurized to kill any germs, and then can be bottled for milk or shipped to butter or ice cream factories.

Corn is grown all throughout the Midwest. Most corn in the Midwest is dent (field) corn. It is not eaten on the cob, but is used for livestock feed, ethanol, and processed into human foods. It is planted in the spring and harvested in the fall. After corn is harvested with a combine, it is transported to a grain elevator, where it is stored until it’s ready to be sold. Corn can be sold to a variety of places, one of which is a food factory. It is often transported by semi, train or barge. There, it is ground up and turn into corn starch, which is an important thickening ingredient in many recipes.  

Procedures:

  1. Set up three stations around the room; one to make butter, one to make ice cream, and one to make oobleck. Break students into three equal groups. (These three activities could also be done on three separate days as a whole class).
  2. Have each group go to a station.
  3. Ice cream station:
    1. Have students aid in the making of ice cream. 1 and ½ cups of the ice cream mix should be placed in the quart Ziploc bag, and the bag should be zipped shut.
    2. Place two cups of ice in the gallon bag and add the ice cream milk bag.
    3. Add a cup of rock salt, close and tape the bag shut. Wrap it in towels and pass the bag around the group of students, having each shake and knead the bag until the contents are the consistency of ice cream, approximately 10 minutes.
    4. While students are shaking the bag, discuss with students the process of how milk goes from cow to ice cream. Ask them where they think milk comes from, and discuss how milk is transported, cooled, and turned into other products.
    5. If there’s time, read the book Life on a Dairy Farm with students.
    6. After ice cream has reached appropriate consistency, give each student a taste of the ice cream by cutting the corner of the ice cream bag and pouring it in bowls. Pass out spoons and napkins to students.
    7. Ask students to describe the consistency of the ice cream. How is it different than that of the ice cream mix? What may have caused the change?
  4. Butter station:
    1. Give each pair of students a jar filled 2/3 full of heavy whipping cream. Ask students to describe the consistency of the contents of the jar.
    2. Have students take turns shaking the jars of heavy cream until solid butter forms. Have students attempt to identify the change on their own. They should notice a change in the sound as the butter clumps together and splashes in the leftover cream and see clumps of butter in the jar.
    3. When students have determined that they have solid butter, they should bring the jar to the instructor and explain why they think they have solid butter. If correct, they can drain the liquid out of the jar and use the solid butter to butter crackers.
    4. As students eat their crackers, discuss or review the process of how milk gets from cow to butter. Ask questions like:
      1. Does milk come from an animal? What animal? How do we get the milk?
      2. What happens to milk after it leaves the cow?
      3. What do cows need to make milk? (food, water, to have had a calf)
      4. What role does a farmer play in the life of the dairy cow?
  5. Oobleck station:
    1. Place two tablespoons of cornstarch on the plate. Show the students, and have them describe what they see. Is the cornstarch a solid or a liquid?
      1. Talk with students about what cornstarch is. Describe how cornstarch is made.
    2. Place a tablespoon of water in the plate, and use a spoon to stir it. Show students the results on the plate. Is it a liquid or a solid?
    3. Use the spoon to pull some of the oobleck off the plate. Invite students to touch it. Is it a liquid or a solid?
    4. Explain that oobleck resembles both a liquid and a solid. What are some of the properties of a liquid it has? What are some of the properties of a solid it has?
    5. Show students the kernels of corn. Have them guess how the kernel gets turned into cornstarch.

Extension Activities:

Students could create a list of foods or food products they find in their home refrigerator or cupboards. Have the students categorize them as liquid, solids, or gases.

Sources/Credits:

Adapted from Iowa State University Extension Rocks to Ice Cream Activity from Growing in the Garden

Adapted from Yvonne Gaul

Author:

Kelsey Faivre - IALF

National Agriculture Literacy Outcomes:

  • Plants and Animals for Food, Fiber & Energy Outcomes
    • Identify animals involved in agricultural production and their uses
  • Culture, Society, Economy & Geography Outcomes
    • Trace the sources of agriculture products used daily
    • Discuss what a farmer does

Iowa Core Standards:

  • Science:
    • K-2-ETS1-2. Develop a simple sketch, drawing, or physical model to illustrate how the shape of an object helps it function as needed to solve a given problem.
    • 2-PS1-1. Plan and conduct an investigation to describe and classify different kinds of materials by their observable properties.