Chemical Reaction “Pumpkin Patch” – A Chemistry Activity for Kids

This chemistry activity for kids puts an artistic and colorful twist on the traditional baking soda and vinegar combination.

While completing this chemistry activity, students will learn and observe how:

• A liquid and solid mix to change the properties of the solid
• A liquid and solid mix to create a gas
• The primary colors of red, yellow, and blue can be mixed to make new colors (orange, green)

We designed and tested this activity with preschool and elementary ages, but honestly, we all had fun creating our pumpkin patches.

I highly recommend you have your children wear gloves when handling the food coloring. Our four-year-old twins LOVE mixing colors, but what a mess food coloring makes.

We did find that putting baking soda on their hands, followed by a small amount of vinegar and then some good old-fashioned rubbing, did get rid of the staining on their skin.

Reading Recommendations

One of my absolute favorite college classes was Children’s Literature for Elementary Grades.  From the start of my lesson planning days, I always incorporated several read-alouds into a day.

Whopper Cake is sure to get some giggles, and it presents the idea of mixing substances and creating a chemical reaction. I’ve used this with 4-year-olds before introducing baking soda and vinegar activities. Oh, how they giggled!

If you are doing this chemistry activity with children from preschool to third grade, consider the read-aloud Whopper Cake. The other title pictured is Chemistry (Baby’s Big World). I found the content better suited for a 2^nd-3^rd grade, as it discusses elements, The Periodic Table, molecules, and more. For those early elementary ages, it’s a straightforward explanation. It was way too much for our four-year-old twins.

While we have made our project Fall-themed on this post, you can adapt this for any season. Make a summer flower garden or snowflakes and snowmen for winter.

 Note:

• Add a few drops of Dawn to the playdough to add some extra fizz.
• Have extra baking soda and vinegar on hand to allow students to explore more and take the activity where their curiosity leads them.

If you want to turn this activity into an experiment with a variable that changes, here are some ideas:

• Mix the food coloring with milk? Will the milk and baking soda mix to form a “dough”? Will the vinegar have the same chemical reaction with the milk-based dough as with the water-based “dough”?
• Mix the food coloring with lemon juice? Will the lemon juice and baking soda mix to form a “dough”? Will the vinegar have the same chemical reaction with the lemon-juice-based “dough” as it did with the water-based “dough”?

What You Need to Gather for This Activity:

• 1 ½ to 2 cups of baking soda
• 6 Tablespoons of water (room temp to cool is fine)
• Food coloring: yellow, red, blue (leave out the green
• 2 to 3 cups of vinegar
• Five plastic containers for mixing
• Five small bowls or cups
• Spoons
• Child-size droppers (We have two of these sets that come with droppers.)
• Tablespoon measuring spoon
• ¼ cup measuring cup
• ½ cup measuring cup
• Foil or metal baking sheet
• Paper towels
• Gloves

Questions to ask:

• What do you think will happen when we mix the water and baking soda?
• What do you think will happen when we add vinegar to the water and baking soda?
• In this activity, we are going to make some “dough” out of baking soda, water, and food coloring. We have three colors – red, yellow, and blue. How can we mix the colors to make orange “dough”?
• What colors will you mix to get green?

What To Do:

1. Measure ½ cup of baking soda into one of the mixing containers
2. Next measure ¼ cup of baking soda into each of 4 remaining mixing containers
3. Measure 2 T of water into a small bowl or paper cup.
4. To the 2 T of water, add 2 drops of red food coloring and 8 drops of yellow food coloring. Stir
5. Add the orange water to the ½ cup of baking soda and stir well. The mixture should form a soft “dough” that sticks together fairly well.
6. Measure 1 T water into each of the remaining 4 small bowls or paper cups.
7. Set aside one of the water cups for dough that will not be colorized.
8. Add 2 drops of blue to one of the containers of water and stir.
9. Add 2 drops of green and 8 drops of yellow to another container of water and stir.
10. Add 3 drops of yellow to the fourth container of water and stir.

You should now have the following:

• 1 container with orange “dough”
• 1 container with a tablespoon of plain water
• 1 container with a tablespoon of blue water
• 1 container with a tablespoon of yellow water
• 1 container with a tablespoon of green water made by mixing yellow and blue food coloring.

Next:

11. Pour the plain water into ¼ of baking soda and stir to make a “dough”. You may want to stir with a spoon then mix by hand.
12. Pour the yellow water into ¼ of baking soda and stir to make a “dough”. You may want to stir with a spoon then mix by hand.
13. Pour the blue water into ¼ of baking soda and stir to make a “dough”. You may want to stir with a spoon then mix by hand.
14. Pour the green water into ¼ of baking and stir to make a “dough”. You may want to stir with a spoon then mix by hand.

You should now have five baking soda “dough” containers – orange, white, yellow, blue, and green.

Design and create a pumpkin patch scene with the dough on the cookie sheet.

Once the design is complete, use a dropper or a paper cup to pour vinegar over the baking soda “dough” and watch the pumpkin patch fizz!

With extra baking soda, vinegar, and food coloring on hand, mix up more dough and try different color combinations.

A good formula is one tablespoon of water for every ¼ cup of baking soda.

Watch  a video of this activity:

Explanation of What Happened:

The vinegar (acetic acid) is an acid, and when mixed with baking soda (bicarbonate), which is a base, a chemical reaction occurs, and a gas forms. This gas is carbon dioxide. Carbon dioxide is invisible, but we knew it was there because of the bubbles.  Did you know you exhale carbon dioxide?

A more in-depth explanation for older students (middle and high school) from the University of California, Santa Barbara website.

Discovery Learning

This is the time to let your child take the activity further by testing some of their ideas.

• “What if we add more vinegar?”
• “What if I mix two drops of each color into the water?”
• “What if I use orange juice?”

(Within limits :)) Encourage your child to test their ideas, discuss what they think will happen, and test it!

Try These Additional Chemistry Activities for Kids