In fact, the use of salt to melt ice not only appears in life tips or fun experiments at home , but every year more than 20 million tons of salt are still used by people and authorities in many countries. cold country used to “treat” the snow and ice that interfered with their lives.
Salt can effectively melt frozen water.
There is a temperature that is only equal to the ambient temperature but why is salt able to melt frozen water so effectively? To answer this question, we first need to understand the freezing mechanism of water!
At the “Freezing Point” , the surface portion of the water body will remain liquid.
In theory, when the ambient temperature drops to 0 degrees Celsius, water will begin the process of changing from liquid to solid. This temperature is also known as the “Freezing Point”. At the “Freezing Point” , the surface of the water mass will remain liquid, while the bottom has turned solid. The entire body of water will freeze completely when the temperature drops even further. On the contrary, if the medium warms up, it gradually turns back to a liquid state.
Going back to the problem raised at the beginning of the article, when we add an ionic compound called salt to the ice, the water and salt molecules will interact with each other. As a result, the “Freezing Point” of water is no longer 0 degrees Celsius, but will be lowered. This means that a temperature below 0 degrees Celsius is needed to keep water in a solid state. The surface of the ice is a place in direct contact with salt, so the temperature of the “Freezing Point” is naturally pushed to the lowest. Therefore, this part will be melted first.
The surface of the ice is in direct contact with the salt, so it will melt first.
This special interaction between salt and water can also be easily observed at the poles of the Earth. In these areas, although the ambient temperature drops to minus a few tens of degrees Celsius, only a part of the surface seawater is frozen, while most of it remains in liquid form.