Why does salt melt ice, how, thanks to its characteristics, sodium chloride triggers the melting process through simple contact with water.
Ice and salt explanation
Wanting to explain why salt is able to melt ice, one of its fundamental characteristics must be considered, namely the ability to lower the freezing point of the water, which normally takes place near 0 ° Celsius.
Scientifically explaining the phenomenon it is possible to affirm that the salt molecules, coming into contact with water, break down into ions that electrostatically join to the water molecules.
As soon as the water temperature drops below zero, the first water crystals are formed which start the formation of ice.
The salt is used to a large extent on the roads during the cold periods of the winter season, when the temperatures are quite rigid, causing the melting of the already formed ice and making the freezing point drop by a few degrees.
When the salt is spread on the road, thanks to its composition, all the crystals that characterize the thin layer of surface liquid that characterizes the ice are first dissolved.
Subsequently, through a natural mechanism, the formation of ice is interrupted, giving rise to the melting phase of the molecules typical of the freezing of water, a phenomenon that causes the melting of ice.