Preparation And Properties Of Ammonia

Preparation And Properties Of Ammonia

Shivani PooniaUpdated on 02 Jul 2025, 06:40 PM IST

Imagine entering the kitchen and opening one of the bottles with the household cleaner. One will smell a strong smell with a bad odor. Most likely, Ammonia is going to be the compound. For sure, this is one of those compounds which significantly shapes our daily lives. Of course not only as a household cleaning reagent. Ammonia finds its invaluable application in agriculture and industry. It is applied in fertilizers for food, and in a wide range of industrial processes

This Story also Contains

  1. Ammonia
  2. Preparation Methods
  3. Summary
Preparation And Properties Of Ammonia
Preparation And Properties Of Ammonia

Ammonia

Ammonia is a colorless gas, and it has a typical pungent smell. Ammonias are one nitrogen atom bonded with three hydrogen atoms chemically, NH3. This is a very simple and very interesting molecule because of its polarity and the possibility of hydrogen bonding. The independence and corollaries of the very same polar nature and hydrogen bonding make ammonia highly soluble in water by forming ammonium hydroxide on dissolution, NH4OH. This thereby made possible ground for the remainder of the work on its applications and preparation methods because it brings into play knowledge of the overall chemical structure and properties of ammonia.

Preparation Methods

The Haber-Bosch process offers a significant method of preparation for ammonia and was developed in the early twentieth century, whereby it greatly revolutionized agriculture and industry. The process maintained for the same is basically the direct combination of nitrogen in the air with high pressure and temperature in the presence of an iron catalyst. This reaction is made use of a well-balanced chemical equation as follows:
N2(g) + 3H2(g) → 2NH3(g)
Another process involves heating ammonium salts; for instance, ammonium chloride, upon reaction with a strong base, such as calcium hydroxide, in another to produce the ammonia gas. All these different processes indicate just how urgent the production of ammonia is for the realized ends of industry and for chemical purposes; thus, they only amount to just how much chemistry and engineering meet.

Preparation

Ammonia is present in small quantities in air and soil where it is formed by the decay of nitrogenous organic matter e.g., urea.

$\mathrm{NH}_2 \mathrm{CONH}_2+2 \mathrm{H}_2 \mathrm{O} \rightarrow\left(\mathrm{NH}_4\right)_2 \mathrm{CO}_3 \rightleftharpoons 2 \mathrm{NH}_3+\mathrm{H}_2 \mathrm{O}+\mathrm{CO}_2$

NH2CONH2+2H2O→(NH4)2CO3⇌2NH3+H2O+CO2

On a small scale, ammonia is obtained from ammonium salts which decompose when treated with caustic soda or calcium hydroxide.

$\begin{aligned} & 2 \mathrm{NH}_4 \mathrm{Cl}+\mathrm{Ca}(\mathrm{OH})_2 \rightarrow 2 \mathrm{NH}_3+2 \mathrm{H}_2 \mathrm{O}+\mathrm{CaCl}_2 \\ & \left(\mathrm{NH}_4\right)_2 \mathrm{SO}_4+2 \mathrm{NaOH} \rightarrow 2 \mathrm{NH}_3+2 \mathrm{H}_2 \mathrm{O}+\mathrm{Na}_2 \mathrm{SO}_4\end{aligned}$

2NH4Cl+Ca(OH)2→2NH3+2H2O+CaCl2(NH4)2SO4+2NaOH→2NH3+2H2O+Na2SO4

On a large scale, ammonia is manufactured by Haber’s process.

N2(g) + 3H2(g) → 2NH3(g)

In accordance with Le Chatelier’s principle, high pressure would favor the formation of ammonia. The optimum conditions for the production of ammonia are a pressure of 200 × 105 Pa (about 200 atm), a temperature of ~ 700 K, and the use of a catalyst such as iron oxide with small amounts of K2O and Al2O3 to increase the rate of attainment of equilibrium. The flow chart for the production of ammonia is shown in the figure given below. Earlier, iron was used as a catalyst with molybdenum as a promoter.

Properties

Ammonia is a colorless gas with a pungent odor. Its freezing and boiling points are 198.4 and 239.7 K respectively. In the solid and liquid states, it is associated through hydrogen bonds as in the case of water and that accounts for its higher melting and boiling points than expected on the basis of its molecular mass. The ammonia molecule is trigonal pyramidal with the nitrogen atom at the apex. It has three bond pairs and one lone pair of electrons as shown in the structure. Ammonia gas is highly soluble in water. Its aqueous solution is weakly basic due to the formation of OHions.

NH3( g)+H2O(l)⇌NH4+(aq)+OH−(aq)

$\mathrm{NH}_3(\mathrm{~g})+\mathrm{H}_2 \mathrm{O}(\mathrm{l}) \rightleftharpoons \mathrm{NH}_4^{+}(\mathrm{aq})+\mathrm{OH}^{-}(\mathrm{aq})$

It forms ammonium salts with acids, e.g., NH4Cl, (NH4)2SO4, etc. As a weak base, it precipitates the hydroxides (hydrated oxides in the case of some metals) of many metals from their salt solutions. For example,

$\begin{aligned} & \mathrm{ZnSO}_4(\mathrm{aq})+2 \mathrm{NH}_4 \mathrm{OH}(\mathrm{aq}) \rightarrow \mathrm{Zn}(\mathrm{OH})_2(\mathrm{~s})+\left(\mathrm{NH}_4\right)_2 \mathrm{SO}_4(\mathrm{aq}) \\ & \mathrm{FeCl}_3(\mathrm{aq})+\mathrm{NH}_4 \mathrm{OH}(\mathrm{aq}) \rightarrow \mathrm{Fe}_2 \mathrm{O}_3 \cdot \mathrm{xH}_2 \mathrm{O}(\mathrm{s})+\mathrm{NH}_4 \mathrm{Cl}(\mathrm{aq})\end{aligned}$

The presence of a lone pair of electrons on the nitrogen atom of the ammonia molecule makes it a Lewis base. It donates the electron pair and forms a linkage with metal ions and the formation of such complex compounds finds applications in the detection of metal ions such as Cu2+, and Ag+.

Uses

  • Ammonia is used to produce various nitrogenous fertilizers (ammonium nitrate, urea, ammonium phosphate, and ammonium sulfate)
  • It is used in the manufacture of some inorganic nitrogen compounds, the most
    important one being nitric acid.
  • Liquid ammonia is also used as a refrigerant.
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Relevance and Applications

Any other major application of ammonia involves agriculture. It is used in the production of ammonia-based fertilizers such as urea, ammonium nitrate, and ammonium sulfate. These fertilizers are in high demand, as they are supposed to improve the yields of crops in order to be guaranteed bountiful harvests for food production. Applications of ammonia occur in the industrial sector concerned with the production of nitric acid. It also finds application in refrigerating systems as ammonia absorbs heat well.

This small molecule of ammonia contains a large number of hydrogen bondings. Research for its different applications thus falls under the realms of inorganic and physical chemistry. It also has a very major role in the nitrogen cycle and its related impacts on the environment, more so around its release from agricultural activities, and thereafter what impacts it has caused in turn, for example, on ecosystems. These many uses underpin the importance to which application and study are placed in the science of ammonia.

Recommended topic video on (NH3 Ammonia)

Some Solved Examples

Example 1
Question: How many isomeric disubstituted borazines B3N3H4X2 are possible?

1)6

2)4(Correct)

3)5

4)3

Solution: Disubstituted borazine has 4 isomers: Ortho, meta-1, meta-2, and para isomers. Therefore, the number of possible isomers is 4.

Example 2
Question:
What is the favorable condition for the formation of NH3?

1)Low temperature, high pressure

2)High temperature, low pressure

3)Low temperature, low pressure

4)High temperature, high pressure

Solution: The reaction for the formation of ammonia is:
N2(g) + 3H2(g) → 2NH3(g)
The reaction is exothermic, so a favorable condition is a low temperature. Additionally, increasing the pressure shifts the equilibrium in the direction of fewer gaseous moles. Since the number of gaseous moles decreases on the right-hand side, the favorable condition will be high pressure. Therefore, the correct condition is low temperature and high pressure.

Example 3
Question:
What are the products formed in the following reaction?
CaCN2 + 3H2O →

1)Ca(OH)2 + CO2

2)CaCO3 + NH3

3)Ca(OH)2 + NH3

4)Ca(OH)2 + NH3 + CO2

Solution: The reaction for the hydrolysis of calcium cyanamide (CaCN2) with water is:

CaCN2 + 3H2O → CaCO3 + 2NH3
Therefore, the products formed are calcium carbonate (CaCO3 and ammonia (NH3).

Summary

From being merely one of the very pungent elements that make for household cleaners to an immense service given globally and industrially is ammonia. It is critical to perform discussions on the preparation of ammonia via the Haber-Bosch process and the reaction of ammonium salts with a base. From fertilizers, through industry, to research in academics, such are its endless applications. A foothold of information about the preparation and properties of ammonia will outline the chemical character of the compound and set forth quite cogent arguments for the utility value in a number of various fields.


Frequently Asked Questions (FAQs)

Q: What is the importance of ammonia in the production of fertilizers?
A:
Ammonia is crucial in fertilizer production for several reasons:
Q: How does ammonia behave in non-aqueous solvents?
A:
In non-aqueous solvents, ammonia's behavior can differ significantly from its behavior in water:
Q: What is the relationship between ammonia and amines?
A:
Ammonia is the simplest member of the amine family. Amines can be considered derivatives of ammonia where one or more hydrogen atoms are replaced by alkyl or aryl groups. The relationship includes:
Q: How does the electron configuration of nitrogen contribute to the properties of ammonia?
A:
The electron configuration of nitrogen (1s² 2s² 2p³) directly contributes to ammonia's properties:
Q: What is the role of ammonia in biological systems?
A:
In biological systems, ammonia plays several important roles:
Q: How does ammonia interact with transition metal ions to form complex ions?
A:
Ammonia interacts with transition metal ions to form complex ions through its lone pair of electrons. The nitrogen atom in ammonia donates this lone pair to the metal ion, forming a coordinate covalent bond. This process can be represented as:
Q: What is the significance of ammonia's critical temperature and pressure?
A:
The critical temperature of ammonia is 132.4°C, and its critical pressure is 11.28 MPa. These values are significant because:
Q: How does ammonia participate in acid-base titrations?
A:
Ammonia can participate in acid-base titrations as a weak base. When titrated with a strong acid like hydrochloric acid, ammonia accepts protons to form ammonium ions:
Q: Why is ammonia used as a refrigerant, and what are its advantages and disadvantages?
A:
Ammonia is used as a refrigerant due to several advantages:
Q: How does the presence of ammonia affect the pH of water?
A:
When ammonia dissolves in water, it increases the pH, making the solution basic. This occurs because ammonia acts as a weak base, accepting protons from water molecules to form ammonium ions (NH₄⁺) and hydroxide ions (OH⁻):