Do you live in an area that gets really cold in the winter? If you do, then you may have seen large trucks driving down the icy roads sprinkling salt over the ice. Have you ever wondered why they did that? It’s simple; salt + ice = a chemical reaction! The salt makes the ice melt and break down, making the roads safer for drivers.
Try this experiment with a few basic kitchen supplies to see how the salt reacts with the ice cube to pick up a piece of string.
Fill a glass with water all the way to the top.
Drop 1 ice cube into the water.
Sprinkle with ½ tsp. salt.
Cut a piece of string longer than the width of the cup. Lay the string over the ice cube.
Wait 60 seconds.
Lift both ends of the string and see what happens!
Cool, right? Now go and show your friends how you did this little trick—I mean, science experiment!
What’s the science behind this?
Salt lowers the freezing point of water to below 0 degrees Celsius. When you add salt to the ice cube, it melts a thin layer on the ice cube. The water then re-freezes around the string, allowing you to pick it up!
We sprinkle salt on the roads to keep ice from forming. It’s science at work, keeping us safe!
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