Physics
Chemistry
Snow and Ice

Why does salt melt ice?

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December 10, 2010 7:21PM

Salt lowers the freezing point of water, if you add salt to water, it will be harder to turn it into ice. For example, you need to make metal very hot to melt it, however you don't need as much to melt ice. you don't need as much heat to melt salted ice as you do to melt ice. So salted ice melts faster.
Salt will melt Ice

Salt will dissolve in water

Salt melts ice into water by contact, as it melts the ice, it dissolves, as it dissolves into the water it changes the chemical composition of the water decreasing the temperature at which it will freeze. Technically this is changing the thermal conductivity of water... The more salt in water, the colder the water needs to be before it can freeze. This concentration of Salt in water is referred to as salinity.