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. Of course, drivers still have to be very careful about applying the brakes while the salt is working its magic on the ice, but at least the use of salt helps to lessen the opportunity for accidents to occur.
When it comes to the need to melt ice of a street or major thoroughfare , nothing beats the use of salt. There is not even a need to use a concentrated form to do the job. In many places, plain old sodium chloride or table salt is regularly employed when there is a need to melt ice from roads and sidewalks. Ice in contact with salty water therefore melts, creating more liquid water, which dissolves more salt, thereby causing more ice to melt, and so on.
The higher the concentration of dissolved salt, the lower its overall freezing point. There is a limit, however, to the amount of salt that can be dissolved in water. Water containing a maximum amount of dissolved salt has a freezing point of about zero degrees Fahrenheit. Therefore, the application of salt will not melt the ice on a sidewalk if the temperature is below zero degrees F. To understand why water containing dissolved salt has a lower freezing point than pure water, consider that when ice and water are in contact there is a dynamic exchange at the interface of the two phase states.
Because of thermal vibrations in the ice, a large number of molecules per second become detached from its surface and enter into the water. During the same period of time, a large number of water molecules attach themselves to the surface of the ice and become part of the solid phase.
At higher temperatures, the former rate is faster than the latter and the ice melts. At lower temperatures the reverse is true. At the freezing point the two rates are equal. If salt is dissolved in the water, the rate of detachment of the ice molecules is unaffected but the rate at which water molecules attach to the ice surface is decreased, mainly because the concentration of water molecules in the liquid molecules per cubic centimeter is lower.
Hence, the melting point is lower. Water normally freezes at 32 degrees Fahrenheit, but when you add salt, that threshold can drop as low as 20 degrees Fahrenheit. This means if a snow storm in the area has an outside temperature of 30 degrees Fahrenheit, surfaces treated with a salt solution would only freeze if the temperature outside dropped another 10 degrees. If you sprinkle salt on ice, it will melt for the same reasons.
As the ice melts into puddles of salty water, it will spread to the surrounding roads, mixing with other nearby ice. How fast the ice melts and how low the freezing point of that puddle gets will depend on how much salt you add. Just as salt lowers the freezing point of water in cold temperatures, it also raises the boiling point in hot temperatures. You can see this principal in action when cooking pasta.
Rock salt lowers the freezing temperature of the water, which means the temperature should become colder for the ice formation. There is no difference between the salt in your kitchen and the salt for snow on the roads. The road salt crystals are a bit larger, and the kitchen salt crystals are much finer. At Canada Salt , all our products are made to be your best defence partner against the forming ice. Our rock salt and other de-icing agents help to control the black ice and make the roads safer during the winter.
We deliver bulk salt for snow to anywhere in North America, and also we offer pick-up services in selected cities. Contact or Call us at for pre-booking or inquiries.
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