ALTOONA, Pa. (WTAJ) — In this episode of Science with Shields, Christy Shields shows you how to fish for ice.
What you need:
- Glass of water
- Ice cubes
- Food coloring (optional)
This is an easy experiment, however it does require some patience. You want to fill a glass with water about 3/4 full. Tap water will work at room temperature or slightly cooler.
You will then want to take ice cubes and drop them in the water. With your salt, you can sprinkle it onto the ice cubes. You could also add food coloring to the sale to be able to see the salt better on the ice cubes, but that is optional.
Next, put your string on top of the part of the ice cube with salt on it. You’ll want to wait a full minute or two and the string will freeze onto the ice cube. Slowly you can lift the ice cube out of the water with the string and it should stick. Ta da! You went “ice fishing!”
When you add salt to the ice cube, it lowers the melting point of the ice. Remember, 32 degrees farenheit is the temperature water freezes. Above that it will melt.
The salt you put on the ice cube lowers the freezing temperatures and since the ice cube cannot get colder, it melts. The water that forms from the melting dilutes the water and salt solution.
This then allows the freezing point to go back up and allows the ice to refreeze over the string. This will make the string stick to the ice and you can pull it slowly from the water.
Try it out and let me know how it goes!