How To Make The Pepper Powder Dance On Water?

This Pepper Powder Dance is a super easy but fantastic science experiment with materials that can be found in anyone’s kitchen. It shows us the power of the surface tension.

Age: 3+           Time: <10min

 Safety 

1.Need adult supervision.

2. Be careful, the pepper powder may run into your eyes.

 Materials List 

• Tray
• Water
• Pepper powder
• Washing soap

 Instruction 

Step 1/3 – Add some water in the dish.

Step 2/3 – Sprinkle some pepper powder on the water.

Step 3/3 – put some washing soap on your fingertip and put your fingertip with the washing soap into the water. The magic happens.

 Troubleshooting 

Why did my pepper powder not spread? 

— it can be that there is already some washing soap in the water. When the water contains washing soap, you need to change some water without washing soap in it.

 Scientific Description 

Because the pepper powder is so light that the buoyancy and surface tension of the water support it on the water. Washing soap is designed to reduce the surface tension of the water. This trait makes them good cleaning tools. The water molecules, however, want to stick together. When the washing soap is added, The water molecules, however, want to stick together and maintain that tension, so they move away from the soap, carrying the pepper with them. You may also find that now the surface tension of the water is lower so some pepper powder sinks to the bottom of the water.

 Extensions 

We can replace the pepper powder with DIY glitter powder. There are so many materials available to replace the pepper powder. Can you find some?