Day 9: Foamy Chemistry – Elephant Toothpaste Reaction
Our Big Questions Today:
What do you think will happen when we mix these ingredients?
Prediction: Which hydrogen peroxide, the 3% or the 6%, do you think will create a bigger and faster reaction? Why?
How can we measure the “success” of the reaction? What could we observe or measure to compare the two experiments?
SAFETY FIRST! (Read Carefully!)
Your safety is the most important thing. We are working with materials that need respect.
- GOGGLES ON AND STAY ON: You MUST wear your safety goggles the entire time materials are out, until everything is cleaned up. This is to protect your eyes from any splashes.
- GLOVES: If gloves are available, wear them to protect your skin.
- NO TOUCHING, TASTING, OR EATING: Do not touch the materials with your bare hands, and absolutely do not taste or eat anything used in this experiment.
Your Scientist Station – Materials You Will Use:
(Check that your group has these items)
- Safety Goggles (1 pair per person)
- Disposable Gloves (optional)
- 1 empty plastic bottle
- Small amount of Hydrogen Peroxide (3% and 6% concentration)
- Liquid Dish Soap
- Food Coloring (optional)
- 1 packet of dry active yeast
- Small cup with warm water
Part 1: Your Hands-On Experiment (Working with 3% or 6% Peroxide)
You will perform this experiment with your group at your station.
Step 1: Prepare Your Station
- Make sure everyone in your group has their safety goggles on.
Step 2: Activate the Yeast
- The yeast we are using is like a tiny living thing that needs to “wake up.” It contains something special that helps speed up reactions.
- Pour the warm water into your water bottle up to the fill line.
- Add the packet of dry yeast to the warm water.
- Swirl gently for about 1 minute. What do you see happening in the cup?
Step 3: Prepare the Bottle
- Add about 2-3 drops of liquid dish soap to the bottle.
- If you want colored foam, add a few drops of food coloring now. You can swirl the bottle gently to mix the color, but don’t shake it hard.
Step 4: Make Your Prediction!
- You have the water, yeast, soap, and food coloring (optional) in the bottle, and the hydrogen peroxide nearby in it’s own container.
- What do you think will happen when you pour the yeast mixture into the bottle?
- Share your prediction with your group. What do you think you will see, hear, or feel (by touching the outside of the bottle)?
Step 5: The Reaction!
- Now, it’s time to test your prediction.
- Carefully and quickly pour the Hydrogen Peroxide (3% or 6%) into the plastic bottle.
- IMMEDIATELY step back slightly and watch what happens!
Step 6: Record Your Observations
- Look closely! Use your senses (eyes and feeling the outside of the bottle safely) to be a great scientist.
- What do you see happening in the bottle and the tray?
- Is it happening slowly or quickly?
- What does the foam look like? (Color, size of bubbles, how high it goes?)
- Carefully touch the outside of the bottle (near the bottom) with the back of your hand – does it feel warmer or colder than before?
- Take photos and video and share using the qr code below.
After the Foam: Analyze Your Results 🔬
Once the reactions have slowed down, think about what you saw. Be ready to discuss and share your findings.
Was your prediction correct? Which hydrogen peroxide created a more dramatic reaction?
What differences did you observe between the 3% and 6% reactions? (Think about speed, amount of foam, heat, etc.)
Why do you think one concentration worked better than the other?
If you wanted to make the biggest possible reaction, what other variables could you change or test?
What do you think the yeast does in this reaction?
Career Connection: Chemical engineers often do similar experiments to figure out the best way to make products. What kind of jobs might use this type of experimental process?
Scan the QR code to post your photos and videos on the padlet below
