Phase Change
Properties of Matter

Unsliced ice

At home for 5-11 11-14


What you need

  • An ice cube
  • Polystyrene
  • About 20cm of thin wire
  • Two equal weights e.g. full drinks bottles
  • A sturdy piece of wood and a brick

Instructions

  1. In a cold room, weight the wood down on a table with the brick. Let the end jut over the edge and put a slab of polystyrene on it
  2. Fix the weights to each end of the wire – use strong tape if necessary
  3. Hang the wire over the middle of the ice cube. Wait for some time. The wire should cut its way through the ice but leave the ice cube in one piece

Results and Explanation

Because ice is less dense than water, pressure from the wire squeezes and helps to melt it. (Scientists are still trying to understand all the reasons why it melts!) As the wire moves down, the water refreezes above it.

These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.

Phase Change
can be analysed using the quantity Energy
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