Road salt works by lowering the freezing point of water via a process called freezing point depression. The freezing point of the water is.
First, it's important to understand a bit about H2O in the winter. Thirty-two degrees Fahrenheit (0 degrees Celsius) is its freezing point—that is, when water.
Salt melts ice essentially because adding salt lowers the freezing point of the water. How does this melt ice? Here's what happens.
This means that salt helps in lowering the freezing point and, consequently, the melting point of water (the main component of snow and ice).
When you add salt to an ice cube, you end up with an ice cube whose temperature is above its melting point. This ice cube will do what any ice.
When sprinkled on ice, it makes a brine with the film of surface water, which lowers the freezing point and starts melting the ice that the brine is.