Quick Emulsifier Chemistry Demonstration

Soap is good at cleaning because it acts as an emulsifier, enabling one liquid to disperse into another immiscible liquid. While oil (which attracts dirt) doesn't naturally mix with water, soap can suspend oil/dirt in such a way that it can be removed.

It's easy to demonstrate the action of an emulsifer. All you need are two immiscible liquids and a little dishwashing detergent or soap.

Emulsifier Demo Materials

• water
• kerosene or oil
• dishwashing detergent or soap
• flask or clear glass

Perform the Demonstration

1. Add some kerosene or oil together with some water in a flask. Swirl the contents around to try to mix them. What happens?

2. Add a squirt of dishwashing liquid. Swirl or shake the flask to mix the ingredients. How has the layer of kerosene or oil been changed?

What could be easier, right?