What is Calcium Nitrate?
Calcium nitrate can be described as an inorganic compound having the chemical formula Ca(NO3)2.
Another name for this compound is Norgessalpeter. In 1905, it was synthesized by the process of Birkeland–Eyde at Notodden, Norway. Also, it is a nitrate salt of Calcium that contains calcium, nitrogen, and oxygen. Calcium nitrate compound is either a whitish-grey or white-colored granular solid that absorbs the air's moisture and is found usually as a tetrahydrate compound - Ca(NO3)2.4H2O.
Structure of Ca(NO3)2 Molecules
(image will be uploaded soon)
Preparation of Calcium Nitrate
Calcium nitrate can be prepared using various methods. The most common method used in preparing this compound involves the limestone treatment with nitric acid and the subsequent neutralization of the product, that is formed with ammonia. Also, this compound is produced as an intermediate during the process of nitro phosphate (which is commonly known as the Odda process).
Calcium nitrate compound is a complex fertilizer, where it can be prepared using any of the methods given below:
Usually, when calcium carbonate, called limestone, is treated with nitric acid, calcium nitrate is formed. The reaction can be given as follows.
Ca(NO3)2 + 2HNO3 → Ca(NO3)2 + CO2 + H2O
Calcium nitrate can also be formed when an ammonium nitrate solution is mixed with a solution of calcium hydroxide. The same reaction can be given as follows.
2NH4NO3 + Ca(OH)2 → Ca(NO3)2 + 2NH4OH
Calcium Nitrate (Ca(NO3)2) Properties
Chemical Data of Calcium Nitrate
Physical Properties of Ca(NO3)2
Chemical Properties of Ca(NO3)2
On adding the calcium nitrate compound to sodium carbonate, the calcium carbonate precipitate is formed by leaving the sodium nitrate in the solution. The chemical equation can be given as follows.
Ca(NO3)2 + Na2CO3 → 2 NaNO3 + CaCO3
And, on heating, it undergoes decomposition and releases oxygen and nitrogen dioxide. The chemical equation can be given as follows.
Ca(NO3)2 → CaO + 2 NO2 + ½O2
Calcium Nitrate Uses
Let us look at a few of the calcium nitrate uses:
Calcium Nitrate is used as a fertilizer in agriculture and as an oxidizing agent in match manufacture.
It is used in the light industry to prepare incandescent lamp chimneys and fireworks.
Industrially, it is used in pyrotechnics and explosives industries.
Used for storage quality improvement of crops by reducing bitter pit in apples.
We can also use it as a raw material for making the other nitrate compounds.
Calcium nitrate is used in wastewater pre-conditioning for odor pollution control. In the wastewater system, the wastewater pre-conditioning is mainly focused on the development of anoxic biology. The sulphates’ metabolism ceases in the presence of nitrate, thereby preventing hydrogen sulfide production. Also, the simple degradable organic matter is ingested, which otherwise can cause downstream anaerobic conditions and odor pollution as well. The definition is also valid for surplus sludge treatment.
Especially in dipping processes, calcium nitrate is known to be a very common coagulant in latex production. Often, a part of the dipping bath solution contains the dissolved calcium nitrate. Also, the warm former is often dipped in the coagulation liquid, and a thin layer of the dipping liquid remains on the former. Calcium nitrate will break up the latex solution’s stabilisation when the former is dipped into latex, and also, the latex will coagulate on the former.
This compound is also used in the mixtures of molten salt. Because the dissolution of this compound in water is highly endothermic in nature, calcium nitrate is also used as a pack component. The tetrahydrate of this compound is used in the regeneratable cold packs.
FAQs on Calcium Nitrate - Ca(NO₃)₂
1. What exactly is Calcium Nitrate and what is its chemical formula?
Calcium Nitrate is an inorganic compound, which is a salt formed from calcium and nitric acid. Its chemical formula is Ca(NO₃)₂. It typically appears as a white or greyish crystalline solid and is known for being highly soluble in water.
2. What are the main real-world uses of Calcium Nitrate?
Calcium Nitrate has several important applications across different industries. Its most common uses include:
- Fertilizers: It is widely used in agriculture as it provides both calcium and nitrogen, which are essential nutrients for plant growth, especially for fruits and vegetables.
- Wastewater Treatment: It helps to prevent odour formation in sewer networks by creating an anoxic environment.
- Concrete Production: It is added to concrete mixtures to accelerate the setting time, which is particularly useful in cold weather construction.
- Cold Packs: The process of dissolving its salt in water is endothermic (absorbs heat), making it useful in some regenerative cold packs.
3. In which common liquids can Calcium Nitrate dissolve?
Calcium Nitrate is highly soluble in water. Beyond water, it also dissolves well in other polar solvents such as ammonia, ethanol, and methanol. Its solubility is generally greater in methanol than in ethanol at the same temperature.
4. What is the molar mass of Calcium Nitrate, Ca(NO₃)₂?
The molar mass of Calcium Nitrate (Ca(NO₃)₂) is approximately 164.088 g/mol. This is calculated by adding the atomic masses of all the atoms in the formula: one calcium atom, two nitrogen atoms, and six oxygen atoms.
5. What happens when you heat Calcium Nitrate strongly?
When Calcium Nitrate is heated to a high temperature, it undergoes thermal decomposition. This chemical reaction breaks it down into calcium oxide (CaO), nitrogen dioxide (NO₂) gas, and oxygen (O₂) gas. The nitrogen dioxide produced is easily identifiable as a toxic, reddish-brown gas with a sharp, unpleasant smell.
6. Is Calcium Nitrate considered a dangerous or hazardous substance?
Yes, Calcium Nitrate should be handled with care as it can be hazardous. While not severely toxic, it is a strong oxidising agent, meaning it can intensify fires or cause flammable materials to ignite. Inhaling its dust can irritate the throat and lungs, and direct contact can cause skin and eye irritation. Therefore, using safety equipment is recommended.
7. How is Calcium Nitrate different from Calcium Nitride?
Students often confuse these two, but they are very different compounds. The main difference is the nitrogen-containing ion:
- Calcium Nitrate (Ca(NO₃)₂): Contains the polyatomic nitrate ion (NO₃⁻). It is an ionic salt of nitric acid.
- Calcium Nitride (Ca₃N₂): Contains the much simpler nitride ion (N³⁻). It is formed when calcium metal reacts directly with nitrogen gas at high temperatures.
Their chemical structures, properties, and uses are entirely distinct.
8. What is the importance of knowing about the 'tetrahydrate' form of Calcium Nitrate?
The 'tetrahydrate' form is important because it's the most common state of Calcium Nitrate found under normal conditions. The key difference is the presence of water molecules in the crystal structure:
- Anhydrous Calcium Nitrate (Ca(NO₃)₂): This is the pure compound with no water molecules.
- Calcium Nitrate Tetrahydrate (Ca(NO₃)₂·4H₂O): This is the hydrated form, where each unit of calcium nitrate is bonded with four molecules of water. This form is more stable as the anhydrous version is hygroscopic, meaning it readily absorbs moisture from the air to become hydrated.
