Stacking Liquids

Introduction

Did you know that not only can solid objects sink or float, but liquids can, too? It is actually possible to stack different liquids on top of each other in layers. The key is that all the different layers must have different densities. You can stack them by either picking several liquids with a range of densities, or by varying the density of one liquid by adding chemicals like sugar or salt to it. If you choose colored liquids, or add food coloring to each layer, you can even create a whole rainbow of colors in one single glass! Want to see for yourself? In this science activity, you will stack several liquids, one by one, and create a colorful density column.

Credits

Materials

• Glass or cup
• Tap water
• Food coloring
• Scissors
• Ruler
• Rubber band (wide)
• Small piece of wax
• Craft stick
• Small, clear jars or transparent mini cups (2-oz) with lids (at least 2)
• Permanent marker
• Masking tape
• Small piece of Styrofoam®
• Tablespoons (3)
• Dark corn syrup
• Vegetable oil
• Penny
• Paper towels
• Optional: Rubbing alcohol, dish-washing soap, and other liquids
• Optional: Sugar or salt
• Optional: Digital scale