Activity

Heat melting ice cubes

Summary
Compare how fast ice cubes melt when wrapped in different materials and then exposed to warm water/warm classroom air.
Science content
Chemistry: Atoms, Molecules (3-7)
Physics: Heat (3)
Lessons activity is in
Materials
  • aluminum foil
  • materials to test e.g. thin fabric, thick fabric, paper towel, thick plastic, thin plastic (saran wrap)
  • ramekin
  • ice cubes
  • plastic tub
  • kettle and water
Procedure

This activity still in prototyping stage.

Best method so far is to use hot water to melt ice cubes, which are nested in different materials.
Photos show how to make a nest, with a piece of tin foil and an optional inset of cloth/plastic. The nests are pushed into a ramekin (or other small bowl with a flat base) to shape them. Add ice cubes of the exact same size to each nest, and float the nests in a tub of just-boiled water.
Students record which ice cube melts first, second etc. But nests often leak or tip over, in which case that nest is excluded from a group's results.
In all groups, the ice cube in the foil nest melts first. Then the ice cube in a plastic sheet, then tissue paper, thin cloth, thick cloth, and lastly bubble wrap.
To adapt the method, somehow clip/tape the nests to the side of the tub so they don't fall over.
Discussion: The heat energy in the air is transferred to the ice and heats it up and melts it, by conduction. The cloth/thick plastic does not conduct heat well, so slows down how rapidly the ice melts. Tin foil is a metal and is a good conductor - it transfers the heat energy rapidly to the ice, so the ice melts fastest when in a nest made of only tin foil.

Previous experimental method (see last three photos):
Each student group is given ice cubes to wrap in different kinds of cloth (fur, thin cloth, or no cloth).
https://www.acs.org/content/dam/acsorg/education/resources/k-8/science-…
Problems: It takes a long time to completely melt the ice cubes (an hour or more), and the ice cubes must start out exactly the same size to be able to compare their final sizes. Other variables are how quickly the students wrap each ice cube and how hot the classroom is.

Notes

Try doing the experiment on a paper towel and measuring the size of the wet patch. But cloths used to wrap the ice cube soak up some of the water. Don't fold the cloth entirely around the ice cube, as depending on where the folds are in the cloth, the liquid will escape onto the paper towel at different rates.
Instead of foil nests try in plastic cups BUT need to pack them tight with the test materials or air is included, and somehow stop the paper/cloth absorbing the melted ice.

Grades taught
Gr 2
Gr 3