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http://www.stevespanglerscience.com/lab/experiments/milk-color-explosion This is a great experiment that only needs a little bit of milk, food coloring, and dishwater soap. The chemistry behind this is the weakening of bonds and contortion of molecules. I would love to do this in an elementary classroom, but how can I explain the science behind this to younger grades?

Hi Nina, That was a cool video and it is a cool experiment. It may be difficult to explain the complete science behind the experiment to younger grades, but you can use it to explain the difference between a chemical reaction and a chemical mixture. I did an experiment with baking soda and vinegar at my son's preschool this past spring and I was able to get some understanding of what a chemical reaction is. I showed them the difference between mixing water and baking soda (a mixture) and vinegar and baking soda (a chemical reaction). I also showed them that the reaction produced carbon dioxide by blowing up a balloon on a soda bottle. However, there would be no way that I could explain the complete science behind the experiment to preschoolers. Actually, mixtures and chemical reactions are more for 5th graders. I would use the milk experiment to show that difference by first mixing the milk and food coloring. You still have milk. When you mix in the dish soap, the milk separates into fat and water, which is different than milk and dish soap. A reaction happened and you have something different than what you started with. That experiment is a really cool way to show that. Thanks for your post. Dave

Hold on I think that a few points here may need clarification. soap is a surfactant. A surfactant (or surface active agent) is a substance that has the ability to reduce the surface tension of a liquid. Therefore, when a drop of liquid dish soap is added to milk, the surface tension of the milk is reduced. As this occurs, the fat (butterfat) and protein particles in the milk can move more freely and easily. In addition, the soap interacts with the fat and protein particles in the milk, causing the particles to move around. This action can be seen as the dye swirls through the milk. This is not a chemical reaction Milk is classified as a colloid. A colloid is a mixture in which very small particles are spread evenly through another substance. It is a type of mixture between homogeneous and heterogeneous. Specifically, milk is a type of colloid called an emulsion. Emulsions consist of liquids spread through other liquids. The liquids in an emulsion do not completely mix like the particles in a solution do. Instead the particles of one liquid are suspended in the other. Emulsions generally have a cloudy appearance and will often separate if not continuously mixed

Great experiment! I love the idea of incorporating science in the lower grades- this is often overlooked.

This was so cool to watch. Great experiment for beginners for practicing the scientific method.

I tried this experiment, today, in my Grades 6-12 Science classes, and the kids were enthralled. Thanks for the neat link and the great suggestion. Once the kids are engaged, you can tie in some of the observations to the topics in the text. I spent quite a bit of time just talking about the Scientific Method, starting with the observations and asking them to make an hypothesis and follow it through to the experiment, and conclusion. It was great fun! Thanks!

Hi Nina! I will definitely be saving this lesson/activity for my future classroom. Although elaborating on the content might need to become simplified (in order to be developmentally and academically appropriate for the age level), it's inexpensive, interactive and would work wonderfully as a foundation for chem. basics.

I loved this experiment!! It is really engaging for children which it benefits them as well as you as a teacher.

This demonstration would be great for every elementary grade! It will definitely engage the students about thinking about the science behind it! I

Wow Nina, that video was good! I would never have came up with that experiment, I can't wait to use that in my future lessons. I was fully engaged by the colors and everything so I can only imagine how the children will be. Thanks for sharing! -Jasmine

Hello All: I am an alternative education chemistry/math teacher for high school. My students often come to me with huge content/curriculum gaps which I have learned to enhance by showing such demonstrations and then reflecting on it and introducing concepts new to them (which should have been taught in earlier grades). Any other ideas for me? I don't always know what type of lab safety issues I may encounter with students who come from diverse backgrounds, so I tend to do alot of demonstrations. Any other demo ideas which would be appropriate for high school chemistry would be greatly appreciated.

Chemistry is utterly fascinating. Amazing how we can accrue such knowledge through time.

I think you could liken it to oil and water. After cooking meat when you go to wash the pan, if you fill it with water there is a layer of grease on the top...because the fat and water separate--due to the polar/nonpolar interaction. If you put a drop of soap into it, the soap allows the oil and water to mix because of its properties. That change is immediately visible in the oil/water scenario. I'm pretty sure that this is the same thing that happens in the milk. In the milk colloid suspension you have fat molecules interspersed throughout the watery milk. The drop of soap attracts the fat molecules which move toward the soap and start the movement within the milk, causing the rotation to of the milk molecules as it turns around. Instead of using big words like polar and non polar or hydrophobic and hydrophillic...you could use the more common terms like charged/ not charged or water loving vs water fearing. I'd maybe show them the milk demonstration and then show them the oil/water-soap demonstration and ask them to think about how those experiments are similar or different to eachother.