5/17/11

Experiments on How to Melt Ice

  • Boiling Water Versus Cold Flowing Water

    • The boiling water versus cold flowing water experiment teaches students how ice melts. To perform this experiment, you need ice cubes, a pot of boiling water and a sink. Bring a pot of water to a boil. Turn on the cold water in your sink. Find two ice cubes of the same size, and drop one in the boiling water while holding the other one under the stream of cold water. You will discover the ice cube in the sink melts before the one in the boiling water. According to A to Z Teacher Stuff, "ice melts as heat moves inward from the surrounding area." The boiling water causes the outside of the ice cube to melt quickly, but the melted ice creates a layer of cold water that insulates the rest of the ice cube from the hot water, causing it to melt slower. As the cold water from the sink slowly melts the ice cube, it also carries away the melted ice, so an insulating pocket of cold water doesn't form. This causes the ice cube to melt faster under running cold water than in a pot of boiling water.

    Salt Versus Ice Experiment

    • Teach students about water molecules by performing the salt versus ice experiment. Equipment needed includes an ice cube, bowl, thread and salt. Set the ice cube inside the bowl and lay the thread across the top of the ice cube. Spread a small amount of salt around the thread and wait approximately two minutes. After two minutes, carefully lift the ends of the thread. The thread will be frozen to the ice. This happens because a thin layer of liquid sits on the surface of your ice cube. According to Commonwealth Scientific and Industrial Research Organization (CSIRO), "the salt stops some of the liquid water molecules from re-joining the ice, but it doesn't affect the water molecules breaking off from the ice." This speeds up the melting process. The melting ice dilutes the salt so the salt becomes less effective. However, after more time lapses, the salt becomes so diluted the liquid can reconnect with the ice and freezes around the thread.

    Ice Melting Agents Experiments

    • Different materials cause ice to melt; some materials make ice cubes melt faster than others. Use five trays of ice cubes, five bowls and 12 ounces of road salt, calcium chloride, sand and kitty litter, to complete the ice melting agents experiment. Fill each bowl with a tray of ice. Sprinkle 12 ounces of each substance into four of the bowls. You'll use the fifth bowl of ice as your control group, allowing it to melt at room temperature on its own. Monitor the bowls to see how much time it takes for all of the ice cubes to melt in each bowl. Create a data chart recording the melting times of each bowl.

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