Iron is stronger than ice, right? Not on a cold winter’s day. Vividly demonstrate what happens to water when it freezes—it expands with enough force to crack a cast iron pipe! Immerse a completely water-filled cast iron pipe into a dry ice/ethyl alcohol bath. Allow it to cool for several minutes. When the water freezes to a solid inside the pipe—BANG!—the iron pipe cracks to reveal the solid ice. Includes Teacher Demonstration Notes and enough materials to perform the demonstration twice.
Concepts: Expansion of water as it freezes, ruptured water pipes, phase diagrams. Time Required: 20 minutes Materials Provided: Two elbow pipes with caps. Note: Dry ice and 95% ethyl alcohol not included.