Learn Together
Explore the difference in density between oil and water and watch the surprise chemical reaction released from fizzing tablets. Trying fun experiments is an engaging way to make scientific concepts easy to understand while having lots of fun!
Materials
- Plastic or glass bottle
- Water
- Food coloring
- Vegetable or canola oil
- Funnel
- Fizzing tablets (like Alka-seltzer)
Make Together
- Use a funnel to carefully fill a clear plastic or glass bottle one quarter of the way full with water.
- Add in a few drops of food coloring and watch the colors mix with the water. What does it look like to you? What happens if we cover it and shake it up?
- Once the food coloring is all mixed with the water, use the funnel again to fill the rest of the three quarters of the bottle with vegetable or canola oil. What happens when the water and the oil try to mix? The difference in density of the water and the oil keeps them separated!
- Wait for the oil and water to separate. More dense materials will sink to the bottom, while less dense materials float to the top. In this case, which do you think has a higher density, the water or the oil?
- Break the fizzing tablets into small pieces and drop one piece at a time into the bottle. Fizzing tablets release carbon dioxide. Carbon dioxide is a colorless, odorless gas. It’s what makes soft drinks fizzy and makes up the air you breathe out.
- Watch what happens! As the fizzing tablets release carbon dioxide, small bubbles of colorful water travel up through the oil. Just like a lava lamp!