As winter approaches, many cities, including New York and Chicago, begin to stockpile salt to combat the icy conditions that can make roads and sidewalks hazardous. The question often arises: why do we use salt to melt ice?The answer lies in the basic principles of chemistry. Salt, or sodium chloride, lowers the freezing point of water. Normally, water freezes at 32 degrees Fahrenheit (0 degrees C...More