What is Calcium Chloride?
It is an inorganic compound, a salt with the chemical formula CaCl2, which exists as a white coloured crystalline solid at room temperature.
Calcium Chloride is soluble in water. It can be made by neutralising hydrochloric acid with calcium hydroxide. It is commonly encountered as a hydrated solid. For de-icing and dust control these compounds are used. The molar mass of calcium chloride is 110.98g mol-1. It is odourless and has an average density of 2.15g. The other anions of this compound are calcium fluoride, calcium bromide and calcium iodide. It is an irritant and has a viscosity of 3.34cP (787-degree centigrade).
What Are The Uses of Calcium Chloride?
There are numerous applications of calcium chloride.
It is popularly used as an additive in plastics, wastewater treatment plants and also in blast furnaces to improve the process and the characteristics.
It is also used as an agent to decrease the freezing point of water.
Further, calcium chloride is greatly helpful for preventing ice formation on the road surfaces and is also, therefore, used as a de-icer. However, it consumes the greatest amount of calcium chloride by depressing the freezing point of water which prevents ice formation and is also used to de-ice.
It is also used in domestic and industrial chemical air known as dehumidifiers.
It has been observed that the intake of the average calcium chloride in food is around 160 to 345mg per day.
In aquariums, it is used as an approach to introduce bioavailable calcium for calcium carbonate- shelled animals like, molluscs and cnidarians.
It is also used in canned vegetables and in producing a caviar substitute from fruit juices or vegetable. In sports drinks and other forms of beverages including water, it is used as an electrolyte.
To add salty taste in pickles, calcium chloride is used.
From brewing beer to cheesemaking there are endless uses of calcium chloride.
Role of Calcium Chloride As A Water Treatment Agent
Calcium chloride is used for the treatment of water. It is also used in bottled water but majorly, it is used in treating wastewater to remove the undesired amount of impurities present in it. Calcium is regarded as an important determinant of water harness and a pH stabilizer which gives water an elevated taste. One the other hand, calcium chloride is used in the petroleum, metalworking, laundry, textile and food processing industries where it is used in oily waste streams. This creates oil droplets to float to the surface. In the final stage, it is removed through skimming.
Is Calcium Chloride Harmful to Humans?
Calcium chloride if ingested can create burns in the mouth and also in the throat. This would create an excess amount of thirst, vomiting, stomach pain and would also lead to increased blood pressure and is also capable of severe health problems. This is the reason why calcium chloride should not be ingested.
It is to be considered that in extreme cases of ingestion, this chemical is capable of causing skin burns, respiration issues, and seizures and also can cause cardiac disturbances. Further, it can also irritate skin by an extreme amount of dryness or dehydrating moist skin.
These are the possible health hazards that calcium chloride can create and so it is essential to be as cautious as possible while handling this material whether in a laboratory or at home or any other possible place.
What Are The Things to Remember While Handling Calcium Chloride?
While dealing with any form of chemical it is important to follow the safety measures. It could be using safety glasses, an apron and gloves. If it is being used in a workplace then it is important to ensure that the eyewash station is nearby. Other than this, some of the important steps to be followed are inhalation which is seeking fresh air and immediate medical attention. Next, if it comes in contact with the skin then always flush the affected area with a sufficient amount of water. Remove the clothes that are contaminated and wash with soap and use emollient in order to cover the irritated skin. Also, if it comes in contact with the eye, water the eyes immediately for a minimum of 15 minutes in order to prevent the damage.
Where To Store or Dispose of Calcium Chloride?
It is important to store calcium chloride in an area which is away from moisture and incompatible materials. Next, keep the container in an area which is well ventilated and is cool and dry enough. In order to dispose of calcium chloride, it is essential to follow the rules of the federal, state and local area.
Role of calcium chloride in plant growth
Studies have shown that calcium breaks down easily in water. This results in the formation of calcium and chloride ions. While calcium helps in the growth of the plant, chloride is regarded as an important micronutrient for plants and plays a crucial role in the process of photosynthesis.
Importance of Calcium Chloride As A Drying Agent
As stated earlier calcium chloride has umpteen number of usage. One such use of calcium chloride is in drying which is why it is regarded as a drying agent. It is used on sidewalks and road and also in parking lots where it works as a de-icing agent. By reducing the melting point of the water, calcium chloride prevents the formation of ice.
What Is The Use of Calcium Chloride In A Fire Extinguisher?
In a fire extinguisher, calcium chloride is used as an additive. However, it is important to remember that the stainless steel extinguisher after getting expired should be destroyed and not tested or replaced under any cost as it is capable of posing a huge threat.
How To Produce Calcium Chloride?
In order to produce calcium chloride, take a beaker and add ¼ of hydrochloric acid to limestone. Next, you would see that the hydrochloric acid will start to bubble as it dissolves the limestone. After this, swirl the beaker in order to mix the contents. It is essential to ensure that the reaction is completed. After a few minutes, you will see that calcium chloride has been formed in the beaker.
Boiling and Melting Points of Calcium Chloride
The boiling point of calcium chloride is 1,935-degree centigrade and the melting point of the calcium chloride is 772-degree centigrade. The molecular mass or weight of the chemical is 110.98g. It is anhydrous and therefore, its density is around 2.15.
FAQs on Calcium Chloride
1. What is the chemical formula and structure of Calcium Chloride?
The chemical formula for Calcium Chloride is CaCl₂. It is an ionic compound formed when one calcium atom, which is a metal, donates its two valence electrons to two chlorine atoms, which are non-metals. This results in the formation of one calcium cation (Ca²⁺) and two chloride anions (Cl⁻), held together by strong electrostatic forces, also known as ionic bonds, in a crystal lattice structure.
2. What are the key physical and chemical properties of Calcium Chloride?
Calcium Chloride is a salt that appears as a white, crystalline solid at room temperature. Its most notable properties include:
- Hygroscopic Nature: It strongly attracts and absorbs water vapour from the atmosphere.
- Deliquescence: When it absorbs sufficient moisture, it dissolves in the absorbed water, forming a liquid solution.
- High Solubility: It dissolves readily in water in an exothermic process, meaning it releases heat.
- Ionic Character: As an ionic salt, its aqueous solution is a good conductor of electricity.
3. How is Calcium Chloride typically prepared?
Calcium Chloride can be prepared through several methods. A common laboratory method involves the reaction of calcium carbonate (CaCO₃), such as limestone or marble chips, with hydrochloric acid (HCl). The chemical equation for this reaction is: CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂. Industrially, large quantities of Calcium Chloride are also produced as a major by-product of the Solvay process, which is used to manufacture sodium carbonate.
4. What are the most common real-world applications of Calcium Chloride?
The unique properties of Calcium Chloride make it useful in various applications. Some common uses include:
- De-icing Agent: It is highly effective for melting ice and snow on roads because it significantly lowers the freezing point of water.
- Dust Control: Its hygroscopic quality helps to keep unpaved roads and surfaces damp, thereby suppressing dust.
- Drying Agent (Desiccant): In industrial and laboratory settings, it is used to remove moisture from gases and organic liquids.
- Food Additive: It is used as a firming agent in products like canned vegetables and tofu, and in cheese making to aid curd formation.
5. Why is Calcium Chloride a more effective de-icing agent than regular salt (Sodium Chloride)?
Calcium Chloride (CaCl₂) is often preferred over Sodium Chloride (NaCl) for de-icing for two main reasons. Firstly, CaCl₂ is exothermic, meaning it releases heat as it dissolves, which actively helps melt the ice. NaCl, on the other hand, has an endothermic or neutral dissolution. Secondly, CaCl₂ can lower the freezing point of water to a much lower temperature (down to about -52°C) compared to NaCl (down to about -21°C), making it effective in much colder conditions.
6. Is Calcium Chloride the same as Calcium Carbonate?
No, they are fundamentally different compounds. Calcium Chloride (CaCl₂) is a salt that is highly soluble in water and is hygroscopic. In contrast, Calcium Carbonate (CaCO₃), found in chalk, limestone, and marble, is a base that is largely insoluble in water. While both are calcium compounds, their chemical properties and uses are distinct; for instance, CaCO₃ is used to neutralise acid, whereas CaCl₂ is used as a drying agent.
7. Why is Calcium Chloride used as a food additive with the E-number E509?
As a food additive (E509), Calcium Chloride primarily functions as a firming agent and sequestrant. Its calcium ions interact with pectin in fruits and vegetables, strengthening their cell walls and helping them maintain a firm texture during canning and processing. It is also used in cheese making to improve curd formation and in sports drinks as an electrolyte to replenish minerals lost during exercise.
8. What does it mean for Calcium Chloride to be anhydrous or a hydrate?
The term anhydrous refers to Calcium Chloride (CaCl₂) in its pure form, without any water molecules bonded to its structure. Because it is highly hygroscopic, it readily absorbs water from the air to form hydrates. A hydrate is a crystalline compound that incorporates a specific number of water molecules into its structure. For example, calcium chloride dihydrate (CaCl₂·2H₂O) is a form where each unit of CaCl₂ is bonded to two water molecules.
9. What safety precautions are necessary when handling Calcium Chloride?
When handling Calcium Chloride, especially in its anhydrous form, it's important to take precautions as it can be an irritant to skin and eyes. The most significant safety concern is its exothermic reaction with water; adding water to anhydrous CaCl₂ can generate significant heat, potentially causing thermal burns. It is recommended to wear safety glasses and gloves and to add the solid slowly to water, not the other way around, to control the heat release.
