Developed by Grace B.
Edited by Maggie M.
Essential Question:
How are new substances formed from matter?
Background Knowledge:
Children should know the definition of solids, gases, and liquids. They should be able to describe different properties of objects and know the difference between a mixture and a solution.
A mixture is two or more substances that don’t chemically combine and maintain their physical properties. A solution is a type of mixture where the substances are dissolved completely.
Materials:
- 4 Cups
- 1 teaspoon measuring spoon
- 1/4 measuring cup
- baking soda
- vinegar
- water
- salt
- spoon
- Handout
- writing utensil
- dirty penny
Safety Protocol:
Children should wear safety glasses and gloves if available.
Parental permission required.
Activity Procedure:
Step 1: Gather all materials listed under “Materials.” Create the table (found under “Resources”) using a piece of paper. Before we begin experimenting, make a prediction about which two ingredients will make a solution, and which ingredients will make a mixture. Record your predictions on the table.
What is a mixture? What is a solution? What combo do you think will create a solution? Which do you think will not combine?
Step 2: Start with pouring one tablespoon of baking soda into a cup. Next, add one tablespoon of water and stir. Record what happened to the first mixture on your handout.
What do you hypothesize (guess) is going to happen when water and baking soda are mixed? What happened when these two were mixed?
Step 3: Grab another cup and repeat the process with the water and salt. Record the results on your paper.
Step 4: Grab another cup and repeat with the vinegar and baking soda, recording data as you go. Ask questions along the way such as:
Do you think vinegar is going to react differently with the baking soda than the water did? Why or why not?
Step 5: In another cup, mix the vinegar and salt last. Record those results before the next step.
How did these substances react when combined?
Step 6: Drop your dirty penny into the salt and vinegar mixture. Let it sit for 5 minutes. After 5 minutes take the penny out and notice the change. Update your data about the vinegar and salt mixture.
What happened to the penny? Do the other mixtures do this as well?
Step 7: With parent/guardian permission, share the results of your activity on social media using #AUHomeWorks!
Resources
| Predictions | Observations | Is it a mixture or solution? | |
| 1: Baking Soda and Water | | ||
| 2: Salt and Water | | ||
| 3: Baking Soda and Vinegar | | ||
| 4: Salt and Vinegar | |