In our weekly summer segment Friday Fun with Frederick & Fleming, we do different little science experiments that would be fun to do with your kids. The goal with all of these is to use things you could find around the house or pick up at almost any store for a very little amount of money.
In today’s segment we looked at how soap works to clean dishes by using some fat and food coloring to demonstrate.
- A few cups of whole milk. (It can work with 2% milk but works best with whole milk.)
- Food coloring
- Cotton tip swabs
- Dish soap
- Dinner plate
- Pour the milk onto a dinner plate until there is some depth to it and it covers the plate.
- Place 2 drops of 4 different colors of food coloring in the milk so it looks like the four on the side of a dice.
- Dip the cotton tip into the soap or a soap/water mixture.
- Place the soapy cotton tip into the middle of the four different colors.
Whole milk has the most fat of any of the milks you can buy in a grocery store. Soap is designed to dissolve fat from plates to help remove it from the dishes. So as you introduce the soap to the fatty whole milk, the soap polymers quickly move through milk trying to align themselves with the fat. The motion stops when all the soap has done this.
Try using a diluted soap instead of straight soap. Does it make a difference and why?