Why does salt melt snow?
Salt melts snow because it changes the freezing point of water. Under normal circumstances, water will freeze at 32F, or 0C. By adding salt (and depending what kind of salt you add), you lower that freezing point. Say it is 15F outside, and you have ice. (Freezes at 32F). Now you add salt, suddenly that ‘frozen water’ has a freezing point of 10F. The outside temperature is now greater than the freezing point, and as a result that ice will melt and go back to its liquid phase (water).
