Calcium Chloride is also exothermic, a fancy word that means it creates heat when it comes in contact with water, helping it melt ice faster than any other ice melting chemical.
How fast, you ask?
In the first 20 minutes after application at 20°F (-7°C), Calcium Chloride melts approximately:
30% more ice than magnesium chloride
35% more ice than rock salt
130% more ice than urea
400% more ice than potassium chloride
Calcium Chloride is also gentler on vegetation and a little less corrosive than rock salt (the “salt” we generally think of when the roads and highways get salted).