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Ice Balloons

Going Further

You can take the Ice Balloons activity further in a variety of ways:

Water on ice
When you take the ice balloon out of the freezer, place a drop of water on the sphere and watch it freeze. When it comes from the freezer, the ice balloon is colder than the temperature at which water freezes. The room-temperature water you drop onto the ice balloon cools, and since it is touching an ice crystal seed—the ice balloon itself—the liquid water freezes into a solid.

Water vapor on ice
Notice how water vapor in the air, otherwise known as humidity, freezes onto the surface of the balloon, appearing as frost.

Colors
Put a few drops of food coloring in the balloon before filling it with water to create a colorful ice balloon.

Large vs. small balloon
Make a larger ice balloon (which will last longer because it melts slower) to allow for observation of how the ice balloon melts and the movements it makes as it melts in a tub of water.

Floating and sinking
Use Ice Balloons as a starting point to talk about floating and sinking. Look at other objects and test whether they float or sink. For an object to float, it must be less dense than water. Water is one of the few materials less dense when it is a solid (ice).

Boiling and freezing
Use Ice Balloons to begin thinking about boiling, evaporation and freezing.
http://isaac.exploratorium.edu/~pauld/workshops/weather/solidliquidgas.html

Ice cream
Make ice cream to demonstrate the effect of salt on freezing points. (click to learn about how salt and sugar affect the freezing point of liquid
http://www.exploratorium.edu/cooking/icooks/12-02-02.html

Group determines what are investigable questions
Break participants into groups of four. Let participants determine criteria for investigable questions rather than following the description in the activity write-up. Each small group writes their "investigable question criteria" on poster paper and shares it with other groups.

Sample Questions

Getting learners to ask questions about their ice balloons is an important part of the activity. Here are some examples of participants' questions.

  • Why do some ice balls have more lines (spikes, streaks, bubbles) than others?
  • What if we put the balloon in hot water? In cold water?
  • What if we poured a lot of salt on the ice?
  • Would putting the ice balloon under running water melt it faster than putting it in a tub of water?
  • Why is it harder on the outside and softer on the inside?
  • What are the white wormy things?
  • Does food coloring stick better to salt or sugar?
  • Why does the salt act like acid on the ice?
  • Does it freeze better in some freezers than others?
  • What would happen if we made the ice balloon out of something else, like milk?
  • What would happen if we covered the whole ice balloon with salt?
  • Why does salt melt ice?
  • Why does ice melt so fast in water?
  • Can I get into a spike?
  • Does salt change the temperature of ice?
  • Do different types of salt also melt ice?
  • Does an ice balloon or an orange juice balloon melt faster?

Background Science

Using Salt to Melt Ice
A video segment demonstrating how a pinch of salt can 'catch' an ice cube.
http://www.teachersdomain.org/resource/phy03.sci.phys.matter.zsalt/
Ages: 5–13

Water & Ice
A lesson about how water can take many forms and still be water.
http://www.sciencenetlinks.com/lessons.php?Grade=k-2&BenchmarkID=4&DocID=4
Ages: 5–7

Ice Shelf and Ice Sheet Simulation
An interactive demonstration comparing a melting ice shelf and an ice sheet.
http://www.teachersdomain.org/resource/ipy07.sci.ess.watcyc.icesimulate/
Ages: 11+

Inquiry Resources from Institute for Inquiry
Guides for professional developers, along with diverse resources for inquiry-based learning.
http://www.exploratorium.edu/ifi/
Educators

Ice Stories: Dispatches from Polar Scientists
Blog posts and field reports from polar scientists working in the Arctic and Antarctica.
http://icestories.exploratorium.edu/dispatches/index.php
Ages: 13+,Educators

Density of Snow and Ice
An activity that lets you compare the properties of ice and snow around the world.
http://astro.uchicago.edu/cara/southpole.edu/flaky.html
Ages: 8+


Back to Ice Balloons videos


  • Bee Hummer
  • Bottle Blast Off
  • Color Chromatography
  • Cuica
  • Cup Speakers
  • Ice Balloons
  • Jitterbug
  • Sound Sandwich
  • Stripped Down Motor
  • Water Bottle Membranophone
  • Whirling Watcher

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