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Science tells the story of salt and ice

Terre Haute, Ind. (WTHI) – Salt is the solution to keeping the ice away. But some might wonder how salt works to make ice disappear.

WISH-TV News sister station WTHI News reported a common weather myth is that salt melts ice. Science says there is more to it than just melting.

“It prevents the water from freezing at it’s typical temperature,” explained Peter Coppinger, PhD, Associate Professor of Biology at Rose-Hulman. “When water freezes it forms a nice geometric pattern. When you add in salt, like calcium chloride, it disrupts the ability for them to bind together and causes liquid,” said Coppinger.

This explanation is a little hazy. Coppinger explains in layman’s terms, with children’s building blocks.

“Let’s imagine each block represents a molecule of water, right now this is liquid water, but when the temp drops they come together and form ice, so how does salt melt the ice? It doesn’t melt the ice like you think, it’s not warm, it helps break it apart,” explained Coppinger.

So the answer to this weather myth is salt doesn’t melt the ice. Salt keeps ice from forming by lowering the freezing point.