Surprise: It’s still winter! Wisconsin winters seem to last forever, and those kiddos want to get out and play. Not only do their bodies struggle with less activity, so does their brain. So let’s get them both working!
This Issue's Steam Topic
Exploring and observing the science behind ice melting and water freezing, plus a little Midwestern fishing fun!
Use your scientific and detective skills to figure out how the salt can help the string stick to the ice.
Can you guess what makes the salt melt the ice? The salt reduces the temperature at which water freezes, so it melts it by not freezing it! When the salt melts the ice, some of the water traps the string and then refreezes, causing it to “hold on to” the string. Try it with larger ice cubes. Go outside and see if you can make it work on the snow.
Materials You Could Use (but Are Not Limited To)
• Ice cubes (Freeze them ahead of time, and add toys to them before freezing to make it more fun)
• Table salt
• Plate or bowl (to catch the melted ice and salt)
Incorporating the Arts
This challenge is very open-ended as it can be applied anywhere there is ice. That could mean inside or outside, at the table, or on the ground. You can add to the fun if you want to add food coloring to the ice. To start, freeze ice cubes the night before or at least four hours ahead of time. Once you take the cubes out of the freezer and container, place them on a plate or in a bowl. You can do multiple cubes at a time to make it seem like you are fishing for more and more fish. Once they are in the plate or bowl, add salt on top of them and put one end of the string on the cube and push it down for a few seconds. Then let the string and ice sit for at least 2 minutes. (This gives the melted ice time to refreeze around the string.) Once the time is up, grab the other end of the string and pull the ice cube up out of the bowl, just like pulling a fish out of the ice fishing hole.
Questions to Mull Over
• What is the freezing point of water?
• Does more or less salt speed up or slow down the process?
• How much weight can the string and salt hold? Try it outside with a bigger ice cube or snow ball.
• Talk about how salt is spread on the roads. Now that you have done this experiment, why do you think salt is used like this?
• Does the salt leave residue behind? Can that affect the environment when put on the roads?
• Does different string affect the strength of the hold? Does larger string hold the ice better?
• Could this be used in a magic trick?
Thank you to Amie Winters with the Children’s Museum of Eau Claire for making this STEAM challenge possible.
The Family STEAM Challenge is all about experimenting with the ordinary to make the extraordinary! Chippewa Valley Family challenges your family to think and play together all in the name of science, technology, engineering, art, and mathematics (that’s where the STEAM comes in).
Each challenge can be completed as a family or a group of friends in as little or as much time needed; however, most challenges can be completed within one sitting. The Family STEAM Challenge is also designed to get all ages involved through hands on experimenting. So get ready to put your collective thinking caps on to design a seriously cool apparatus made almost entirely out of reusable or recyclable materials laying around the house.