They work by lowering the freezing point of water.e-icers, or reactive winter road treatments, are liquid forms of salt compounds used to break the bond of already existing snow and ice. They dissolve downward and penetrate until they reach the pavement.
Road salts are typically used to melt or prevent ice from building on winter roads. Some road salts are also used in warmer months as dust suppressants.  ­If you live in a place that has lots of snow and ice in the winter, then you have probably seen the highway department spreading salt on the road to melt the ice.­ You may have also used salt on ice when making home-made ice cream. Salt mixed with ice creates a brine that has a temperature lower than 32 F. When you add salt to the ice water, you lower the melting temperature of the ice down to 0 F or so. The brine is so cold that it easily freezes the ice cream mixture. For more information on road salt, check out the links on the next page Because the freezing point of salty water is a lower temperature than pure water, scattering some salt atop ice or snow can help accelerate the melting process, opening up the roads to traffic that much sooner. Consider how easily salt can corrode your car. Unsurprisingly, it's also a problem for the surrounding environment—so much that in 2004, Canada categorized road salt as a toxin and placed new guidelines on its use. Along with melting ice, placing salt on icy roads also helps to provide a bit of traction for the tires even as the ice is beginning to melt back into water. The grainy nature of the salt allows the treads on the tires to grip the surface of the road, thus minimizing the chances for sliding or fishtailing on the road. Even table salt can be used to melt ice from walkways and sidewalks. Salting icy roads can minimize skidding during winter driving. Salt helps increase traction on roads while at the same time preventing water from freezing. Anti-icers, or preventive winter road treatments, are liquid forms of salt compounds used to prevent the formation or development of bonded snow and ice for easy removal, and are used at the onset of a winter weather storm. They work by lowering the freezing point of water. De-icers, or reactive winter road treatments, are liquid forms of salt compounds used to break the bond of already existing snow and ice. They dissolve downward and penetrate until they reach the pavement. The biggest reason for pouring salt on icy roads is that salt lowers the freezing point of water. Water normally freezes at 32 degrees Fahrenheit, but when you add salt, that threshold drops to 20 degrees (or even 2 degrees) Fahrenheit. And no, there really is no difference between the salt on the road and the stuff on your kitchen table. The only difference is the size. Placing salt on icy roads helps to inhibit the crystallization of water particles into ice, even as the salt breaks down any ice that may have already formed. The same result takes place in the case of placing salt on sidewalks. Even table salt can be used to melt ice from walkways and sidewalks. Salting icy roads can minimize skidding during winter driving. Salt helps increase traction on roads while at the same time preventing water from freezing. When you add salt, that temperature drops: A 10-percent salt solution freezes at 20 F (-6 C), and a 20-percent solution freezes at 2 F (-16 C). On a roadway, this means that if you sprinkle salt on the ice, you can melt it. The salt dissolves into the liquid water in the ice and lowers its freezing point. Salt mixed with ice creates a brine that has a temperature lower than 32 F. When you add salt to the ice water, you lower the melting temperature of the ice down to 0 F or so. The brine is so cold that it easily freezes the ice cream mixture. For more information on road salt, check out the links on the next page For anyone who lives in an area where winter can get very severe, there is the task of dealing with ice on the roads and sidewalks around town. Often, municipalities put down salt on icy roads. Even table salt can be used to melt ice from walkways and sidewalks. Salting icy roads can minimize skidding during winter driving. Salt helps increase traction on roads while at the same time preventing water from freezing.
http://www.ehow.com/list_7668771_types-road-salt.html http://science.howstuffworks.com/nature/climate-weather/atmospheric/road-salt.htm http://www.smithsonianmag.com/science-nature/what-happens-to-all-the-salt-we-dump-on-the-roads-180948079/ http://www.wisegeek.org/why-do-they-put-salt-on-icy-roads.htm https://www.codot.gov/travel/winter-driving/faqs.html http://mentalfloss.com/article/54305/why-do-we-put-salt-icy-roads http://www.wisegeek.org/why-do-they-put-salt-on-icy-roads.htm http://science.howstuffworks.com/nature/climate-weather/atmospheric/road-salt.htm http://www.wisegeek.org/why-do-they-put-salt-on-icy-roads.htm
why do road crews use road salt in the winter months to treat icy roads