How salt melts iceSalt is a great ice melter because it causes “freezing point depression.” This means that salt helps in lowering the freezing point and, consequently, the melting point of water (the main component of snow and ice). In its pure state, water freezes at 0°C or 32°F. By using salt, that freezing point can be lowered which forces the ice to melt and prevents the water from freezing or refreezing. However, salt alone cannot melt ice. It must first be combined with water to start the melting process. Fortunately, ice and snow are generally covered with a thin film of water. As salt touches this water, it starts to dissolve, eventually lowering the freezing point and melting the ice surrounding it.
Ice melters also make use of different substances like calcium, potassium, and magnesium. These ingredients help in decreasing freezing points. They also help in reducing tracking and the corrosive characteristics that salt naturally has (Helmenstine,2017). Water and its polarityWater is a solvent.
A solvent is a substance that can dissolve other molecules and compounds, which are called solutes. A mixture of a solvent and solute is called a solution. Because of its polarity and its ability to form hydrogen bonds, water is a great solvent, meaning that it can dissolve several kinds of molecules.The polarity of water molecules means that molecules of water will stick to each other, also known as hydrogen bonding.
Polarity makes water a good solvent, giving it the ability to stick to itself (cohesion), stick to other substances (adhesion), and have surface tension due to hydrogen bonding (How do the properties of water relate to its polarity? 2017). Halite One of the salts that are used to melt ice is halite. Halite is the mineral name for the substance that is known as “salt”.
Its chemical name is sodium chloride, and a rock composed primarily of halite is known as “rock salt.” Halite is mainly a sedimentary mineral that usually forms in arid climates where ocean water evaporates. However, many inland lakes such as the Great Salt Lake of North America and the Dead Sea between Jordan and Israel are also locations where halite is still forming today. Over time, several enormous salt deposits have been formed when repeated episodes of seawater evaporation occurred in restricted basins. Some of these deposits are thousands of feet thick.
When buried deeply they can erupt to form salt domes. (Halite: The mineral everyone knows as salt, 2017). This salt has many uses. Most of the salt produced is crushed and used in the winter on roads to control the accumulation of snow and ice. Significant amounts of salt are also used by the chemical industry. Salt is an essential nutrient for humans and most animals, and it is also a favorite seasoning for many types of food. Salt is a mineral that everyone knows.
Some of the uses are winter road treatment, a source of sodium and chlorine for chemical processes, food preservation, and even seasoning. Halite or rock salt is a form of sodium chloride, the same chemical compound as table salt. Halite is mined, usually from sources underground. It is commonly used for salting roads but it can be harmful to vegetation, especially in high concentrations.
(Gartenstein, 2017)Potassium Chloride Potassium chloride is a mined salt that is sometimes used to melt ice on streets. Potassium chloride is also a plant fertilizer, although the high doses that plants receive as a result of road salting can be harmful. According to Bob Peeples, a chemical engineer with the United States Postal Service, the highway department in northern Arizona ran into unanticipated difficulty after salting roads with potassium chloride. It may not be the most effective way of melting ice.
The vegetation on the highway medians became so lush that it attracted animals, becoming a traffic hazard. People tend to view Potassium Chloride in the same category as urea because it is also a common fertilizer ingredient as a source of potassium. Potassium Chloride has a relatively high working temperature (25F) and high eutectic point at (12.7F), which makes it not particularly well suited for snow and ice control, but the fact that it’s a fertilizer macronutrient seems to draw some benefit for winter use. All chemical deicers will help remove snow or ice, but can also cause damage to the surrounding environment through many methods. (Snow, Ice, and Dust Control Solutions, 2017) Overall, the reason why salt melts ice is quite simple.
This melting power is the main reason salt will continue to be used for producing the majority of ice melters on the market today. That is why there are different types of salt melters. The deicing salt is the cheapest thing there is.
These types of road salt are easy to store and manipulate its supply and application is simple. Its environmental impact is minimal when it is used and stored properly.