Objectives

To demonstrate the sublimation of dry ice and illustrate states of matter

Materials

• Chunks of dry ice (can be purchased at most major grocery stores)
• Rubber gloves
• Tall cylinder or glass jar
• Large aluminum pan to place the cylinder in (this will help with the mess)
• Liquid dishwashing liquid (Dawn® works best)
• Warm water
• Towels

Procedure

Put the dry ice in the cylinder of warm water (be sure and wear gloves or use tongs). Color the mixture using food coloring. Put a couple of squirts of dishwashing liquid in the cylinder. Grab the towels!

Conclusion

Dry ice is carbon dioxide in solid form. When the dry ice is dropped in the warm water, it changes from a solid to a gas (sublimation). A cloud will form which is carbon dioxide gas and water vapor. When the liquid soap is added, the soap in the water traps the carbon dioxide and water vapor in the form of a bubble. Beware! The bubbles will crawl down the edge of the cylinder.