What Is NH3?

What is NH3? NH3 is a compound of nitrogen and hydrogen with the name known as ammonia. It is a gas that is colorless and it smells like distinct pungent.

What is NH3

:eight_pointed_black_star: What Is NH3 In Chemistry?

Element Ammonia
Chemical formula NH3
Molar mass 17.031 g/mol
Appearance Colourless gas
Odor Strong pungent odor
Melting point −77.73 °C
Boiling point −33.34 °C
Critical point 132.4 °C
Solubility in water 47% w/w (0 °C)
Solubility soluble in chloroform, ether, ethanol, methanol
Vapor pressure 857.3 kPa
Density 0.86 kg/m3

A compound of nitrogen and hydrogen, ammonia with the formula NH3. Ammonia is a colorless gas with a strong odor that is stable binary hydride and the simplest pnictogen hydride. An important source of nutrients for terrestrial species and a primary source of 45 percent of the food and fertilizer used on Earth, it is a frequent nitrogenous waste.

Ammonia, either directly or indirectly, is also a building block for the production of many medicinal goods and is utilized in many commercial cleaning products. Downward movement of both air and water is the primary means by which it is drawn to the surface.

:eight_pointed_black_star: Ammonia’s Chemical And Physical Characteristics

  • Irritating, colorless, and unpleasant at room temperature are only some of the characteristics of ammonia.

  • Anhydrous ammonia, in its purest form, is hygroscopic (readily absorbs moisture).

  • Ammonia has alkaline characteristics and is corrosive.

  • Ammonia gas dissolves quickly in water to generate ammonium hydroxide, a caustic solution, and a weak base.

  • A transparent liquid is formed when ammonia gas is compressed.

  • Compressed liquid ammonia is commonly supplied in steel drums.

  • Ammonia is not a particularly flammable substance, however, intense heat can cause ammonia canisters to explode.

An increase of only 0.1 percent from the previous year’s global industrial ammonia output of 175 million tonnes was recorded in 2018. Anhydrous pressurized or chilled liquid ammonia is delivered in tank cars or cylinders and marketed as either ammonia (typically a 28 percent concentration of ammonia in water) or as a pressurized or chilled anhydrous liquid ammonia.

To keep the liquid from evaporating, it must be held under pressure or at a low temperature, which boils at 33.34 °C (28.012 °F) under one atmosphere of pressure. Ammonium hydroxide, or household ammonia, is a water-based solution of NH3.

A typical high-concentration commercial product has a Baumé concentration of 26 degrees (approximately 30% (by weight) ammonia at 15.5 degrees Celsius or 59.9 degrees Fahrenheit) and is measured in Baumé units (density).


Even though ammonia may be found both on Earth and the outer planets of the Solar System, its concentrated form is both caustic and dangerous. As an exceedingly hazardous material in the United States, it is subject to severe reporting requirements by establishments that create, store or use it in considerable amounts.

:eight_pointed_black_star: Properties Of NH3

Properties Of NH3

Ammonia is a colorless gas with a typically unpleasant odor. Density is 0.589 times more than that of air, making it lighter than air. As a result of the strong hydrogen bonding between molecules, it may be quickly liquefied; the liquid boils at 33.1 °C (27.58 °F), and it freezes to white crystals at 76.7–77 °C

  • Solid: Pearson symbol cP16, space group P213 No.198, and lattice constant 0.5125 nm identify the crystal’s symmetry as cubic.

  • Liquid: Because of its high of 22, liquid ammonia has significant ionizing properties. For this reason and others, uninsulated containers containing liquid ammonia can be used in labs without the need for extra cooling (enthalpy change of vaporization, kJ/mol: 23.35 vs kJ/mol for water, 8.19 kJ/mol for methane, 14.6 kJ/mol for phosphine). Sorbents such as liquid ammonia come to mind.

  • Solve properties: Water is an excellent solvent for ammonia. By boiling, it may be removed from an aqueous solution. Isopropyl ammonium hydroxide (ISO) is basic. ‘.880 ammonia’ refers to the highest concentration of ammonia in water, which has a density of 0.880 g/cm3.

  • Combustion: If you want to burn ammonia, you’ll have to use a fuel-to-air ratio of 15–25 percent. In the presence of oxygen, it emits a mild yellowish-green light as it burns. If sufficient chlorine is present, the highly explosive nitrogen trichloride (NCl3) is also created, which is ignited when chlorine is transferred into ammonia and forms nitrogen and hydrogen chloride.

  • Decomposition: Ammonia decomposes into its constituent elements under high temperatures and in the presence of a suitable catalyst. For ammonia to decompose into hydrogen and nitrogen gas, it requires 23 kJ/mol (5.5 kcal/mol) of ammonia.


Since ammonia has a low heat of combustion, low laminar burning velocity, high auto-ignition temperature, high vaporization] heat, and a limited flammability range, burning it in the air without a catalyst (such as platinum gauze or heated chromium(III) oxide) is extremely difficult.

:eight_pointed_black_star: What Is NH3 Lewis Structure?

Valence Shell Electron Pair Repulsion Theory (VSEPR) predicted that ammonia’s bond angle was 106.7°, which was confirmed by testing. An electron from each hydrogen atom is added to nitrogen’s five outer electrons. There are eight electrons, or four pairs of electrons, organized in this way, for a total of tetrahedrally in NH3 lewis structure.

  • A lone pair of electrons is left after three pairs of electrons are utilized to form bonding pairs. Lone pairs resist each other more strongly than bond pairs, which means that instead of having a bond angle of 109.5°, the bond angle is 106.7°. NH3 lewis structure provides the molecule a dipole moment and makes it polar.

  • Because of the polarity of the molecule and its capacity to create hydrogen bonds, ammonia and water are very miscible. Ammonia is a proton acceptor because of the lone pair.

  • If the unreacted ammonia can be extracted, ammonia can be utilized as a source of hydrogen for acid fuel cells. The most active catalysts were discovered to be those made of ruthenium and platinum, whereas the least active were those made of supported nickel.

Recent studies have revealed that ammonia combustion can be performed using swirl combustors, which has reignited interest in ammonia as an alternative source of energy for thermal power generation. In dry air, ammonia’s flammability range is 15.15–27.35 percent, and in 100 percent relative humidity air, it is 15.95–26.55 percent, respectively.


A precise and dependable reaction mechanism is needed to examine the kinetics of ammonia combustion, however, understanding ammonia chemical kinetics during the combustion process has proved difficult.

:eight_pointed_black_star: Role Of NH3 In Biological Systems

NH3 in biological systems

Throughout the biosphere, ammonia is a metabolic waste and an intake. It is a vital supply of nitrogen for life. Although atmospheric nitrogen is abundant (more than 75%), few living species can use it in its diatomic form, N2 gas.

So, amino acids, the building blocks of protein, require nitrogen fixation. Soil ammonia and other nitrogenous wastes are used by certain plants. The symbiotic association with rhizobia that produce ammonia from atmospheric nitrogen benefits nitrogen-fixing legumes.

  • Biosynthesis: Nitrogenases are enzymes that create ammonia from atmospheric nitrogen. Nitrogen fixation is the total process. The odd structure of the enzyme’s active region, which consists of a Fe7MoS9 ensemble, has sparked intense scholarly interest in the problem. In addition, glutamate dehydrogenase 1 produces ammonia during amino acid deamination.

  • Physiology: Ammonia is involved in normal and pathological animal physiology. It’s made from amino acids and is hazardous in large amounts. The urea cycle is how the liver turns ammonia into urea.

  • Excretion: Ammonium ions are a hazardous metabolic waste product. It is excreted directly into the water by fish and crustaceans. It is converted to urea in mammals, sharks, and amphibians because it is less poisonous and stores better. To be expelled efficiently by birds, reptiles, and terrestrial snails, ammonium is converted to uric acid.

Cirrhosis causes ammonia to build up in the blood (hyperammonemia). Defects in the urea cycle enzymes, such as ornithine transcarbamylase, cause hyperammonemia. Hyperammonemia causes hepatic encephalopathy’s disorientation and coma, as well as the neurologic illness common to urea cycle abnormalities and organic acidurias.

Aquatic creatures commonly excrete ammonia. Humans quickly convert it to urea, which is less poisonous and less basic. Urea is a large component of urine’s dry weight. All vertebrates emit uric acid as nitrogenous waste.


Ammonia is required for appropriate mammalian pH. After glutamine synthesis, -ketoglutarate can be reduced to two bicarbonate ions, which act as buffers for dietary acids. Ammonium excretion in the urine causes acid loss. Further acid excretion is possible if ammonia diffuses across the renal tubules.

:eight_pointed_black_star: Ammonia In Industrial And Manufacturing Applications

Ammonia, when employed as refrigerant gas and in air-conditioning equipment, can absorb large amounts of heat from its surroundings and transfer it to the inside of the device.

Besides being used to cleanse water sources, ammonia is also utilized as a building component in the production of a wide range of goods such as plastics and explosives, as well as textiles, insecticides, and dyes.

Besides waste and wastewater treatment, ammonia is also utilized in the rubber, pulp, and paper sectors as well as the food and beverage industries as a stabilizer, an acid neutralizer, and a nitrogen supply source. Aside from that, it is also utilized in the production of medications.

:eight_pointed_black_star: Ammonia Solution Derivatives

Ammonia Derivatives

Hydrazine and hydroxylamine are two significant ammonia derivatives.

  • Hydrazine: In hydrazine, N2H4, an NH2 group replaces one hydrogen atom in NH3. The pure compound is a colorless liquid that smells with an ammonia-like odor. Its qualities are similar to those of water. It has a low melting point, a high boiling point, and a density of 1 gram per cubic centimeter. Three tonnes of methyl hydrazine mixture were needed for the lunar landing and one tonne for the lunar surface launch.

  • Hydroxylamine: Hydroxylamine, NH2OH, is formed by replacing a hydrogen atom in ammonia with a hydroxyl group (OH). In its pure form, the chemical is a colorless solid that absorbs water quickly. It must be kept at 0°C (32°F) to avoid decomposition. It melts at 33°C (91.4°F), has a density of 1.2 g/cm3, and has a dielectric constant of 78. Hydroxylamine aqueous solutions are not as basic as ammonia or hydrazine. Several processes produce hydroxylamine.

Aqueous potassium nitrite, KNO2, or nitrous acid, HNO2, is reduced with hydrogen sulfite, HSO3. Hydroxylamine is usually kept and utilized in an aqueous solution or as a salt (NH3OH+NO3). It’s commonly used to make oximes.

The main commercial applications of hydrazine are as a blowing agent (to produce holes in foam rubber), a reducing agen, an algicide, fungicide, insecticide, and plant growth regulator.


So this substance (and its methyl derivatives) is mostly used for noncommercial purposes. Guided missiles, spacecraft (including the shuttles), and launchers have all employed hydrazine. In the Apollo lunar module, a 1:1 combination of methyl hydrazine, H3CNHNH2, and 1,1-dimethylhydrazine, (H3C)2NNH2, was oxidized with liquid dinitrogen tetroxide, N2O4.

:eight_pointed_black_star: What Is Ammonia Used For?

Fertilizer Ammonia

A necessary ingredient for growing plants, especially farm crops and lawns, ammonia is a component of ammonium nitrate fertilizer. Around 90% of ammonia generated globally is utilized as fertilizer to help feed billions of people.

Food crop production depletes soil nutrient resources. Fertilizer is used to keep soils productive and healthy for crops. Fertilizers may help crops get critical elements including zinc, selenium, and boron.

In 2019, around 80% of ammonia was utilized as fertilizer in the US, either as salts, solutions, or anhydrous. When sprayed to the soil, it increases crop yields of crops like corn and wheat. Anhydrous ammonia makes up 30% of the agricultural nitrogen sprayed in the US and 110 million tonnes globally.

Ammonia In Cleaning Supplies

It is a component in many household cleaning solutions used to clean surfaces such as tubs, sinks, toilets, counters, and tiles. Ammonia also works well for cleaning out stains from animal or vegetable fats, such as frying grease and wine. Ammonia is widely used in glass cleaning solutions to help prevent streaks.

Household ammonia is an NH3 ammonia solution in water used to clean a variety of surfaces. Because ammonia leaves a streak-free gloss, it is frequently used to clean glass, porcelain, and stainless steel.

Use it to clean ovens and soak things to release baked-on dirt. Household ammonia is 5-10% ammonia by weight. Cleaning product producers in the US must disclose the product’s MSDS which indicates the concentration used.

As A fuel

The X-15’s rocket engine used ammonia as a component fuel.
Ammonia has a raw energy density of 11.5 MJ/L, roughly a third of diesel. The ammonia may be converted back to hydrogen and utilized to power hydrogen fuel cells or used directly in high-temperature solid oxide direct ammonia fuel cells to provide clean energy.

Ammonia engines or ammonia motors have been suggested and utilized. The concept is similar to a fireless locomotive but uses ammonia instead of steam or compressed air. The St. Charles Avenue Streetcar line in New Orleans employed ammonia engines in the 1870s and 1880s, and during WWII, ammonia-powered buses in Belgium.

As A Precursor To Nitrogenous Compounds

Ammonia is a precursor to the majority of nitrogen-containing molecules, either directly or indirectly. All manufactured nitrogen molecules are produced from ammonia, which is the most abundant element on the planet.

Nitric acid is a derivative that is widely used. This critical material is produced via the Ostwald method, which involves the oxidation of ammonia with air over a platinum catalyst at temperatures ranging from 700 to 850 degrees Celsius (1,292 to 1,562 degrees Fahrenheit) and pressures of 9 atmospheres.

Usage In A Laboratory

Depending on the concentration, ammonia solutions are either “dilute” or “concentrated.” “Dilute” ammonia solutions are often 5–10 percent by weight (5.62 mol/L); “concentrated” ammonia solutions are typical>25 percent by weight (5.62 mol/L).

It has been calculated that a 25 percent (by weight) solution has a density of 0.907 g/cm3, which means that a solution with a lower density will be more concentrated. The table below shows the categorization of ammonia solutions according to the European Union.

As A Stimulant

The vapor created by smelling salts, which contains ammonia, has found widespread application as a respiratory stimulant. The Birch reduction method, in which ammonia is used to make methamphetamine, is widely employed in the clandestine synthesis of the drug.

This technique of producing methamphetamine is exceedingly risky since the alkali metal and liquid NH3 ammonia are both extremely reactive, and the temperature of the liquid ammonia renders it prone to boiling when reactants are introduced into the mixture.


Ammonia is extremely caustic, generating ammonium hydroxide, which has a pH higher than water and can cause respiratory system damage, eyesight impairment, and irritation or burning of the skin when it comes into touch with it.

:eight_pointed_black_star: Safety Considerations When Dealing With NH3 Ammonia

Safety Considerations

When ammonia gas is released into the environment, it attaches itself to whatever moisture it comes into contact with, such as that found in a person’s eyes, mouth, throat, lungs, and on his or her skin.

By damaging cell membranes, the caustic action of ammonium hydroxide causes an increase in the amount of liquid that is discharged, which further reacts with ammonia gas, prolonging the effects on the human body.

Important Precautions

During a significant release of NH3 ammonia, such as that caused by a tanker truck rollover or a leaky tanker rail car, you should take the following precautions:

  • Move away from the place where you believe you may have been exposed as soon as possible. If the release was held indoors, proceed to the outdoors.

  • Before using eyeglasses, thoroughly clean them with soap and water.

  • If you want to get rid of ammonia from your skin, avoid using bleach.

  • Remove any clothing that may have been exposed to ammonia as soon as possible. Clothes that are generally removed over the head (such as t-shirts and sweaters) should be cut off the body wherever feasible to avoid further contact with the agent.

  • Wait for instructions on how to properly dispose of the plastic bag before handling it yourself.

  • Putting your clothing in a sealed bag before disposing of it helps to keep you and others safe from any additional exposure.

  • Store the packed clothing in a safe place where others, especially children, will not be disturbed.

  • Large amounts of soap and water should be used to quickly remove any ammonia from your skin. Large amounts of water should also be used to cleanse your eyes.

  • If medical treatment is required, get it as soon as possible.

Personal gas detection with an ammonia sensor is a vital tool for organizations because it allows employees to keep an eye on their work surroundings and the possibility of being exposed to NH3 ammonia gas while on the job.


While ammonia gas has a wide range of applications, including as a refrigerant and fertilizer, as well as a raw material for a variety of operations, it is detrimental to the health of adjacent employees and members of the public when released into the environment.

Frequently Asked Questions - FAQs

People asked many questions about NH3. We discussed a few of them below:

:one: What is ammonia used for?

About 90% of the ammonia generated is utilized as fertilizer, which helps to support the food production of billions of people worldwide. Additionally, NH3 ammonia is used in home cleaning goods and the production of several other items.

:two: Why does NH3 have a high pH?

Protons (hydrogen ions, H+) are donated by acids and accepted by bases, according to the Brasted-Lowry acid-base theory. Water is an acid because it is a hydrogen ion donor, whereas NH3 ammonia is a hydrogen ion acceptor.

:three: Can I make ammonia?

Green ammonia manufacturing is 100% renewable and carbon-free. Green ammonia may be made by electrolyzing water and extracting nitrogen from the air. But today, producing ammonia is not a “green” process.

:four: What is ammonia?

Composed of nitrogen and hydrogen, ammonia—also known as NH3—is a colorless gas. Even in the smallest bacterial molecules, it is naturally created by the human body as well as the environment. Ammonia and the ammonium ion are critical to metabolic health in humans. Ammonia is a byproduct of protein synthesis.

:five: What happens to ammonia in the natural environment?

Ammonia is a naturally occurring substance that may be found in the soil, air, and water of the Earth. As plants fertilize, ammonia is also recycled as part of the natural nitrogen cycle. Because of this natural mechanism, ammonia does not bioaccumulate, and it does not remain in the environment for a long period.

:six: Is NH3 a base or an acid?

Ammonia, NH3, is a Lewis base with a lone pair of electrons. It will transfer electrons to molecules that are capable of accepting electrons. The transfer of ammonia to an electron acceptor, also known as a Lewis acid. Lewis bases can be either anionic or neutral.

:seven: What is ammonia’s odor?

The unpleasant stench of ammonia has been likened to that of perspiration or cat urine. Brie, which has a strong saline flavor, has been known to have an ammonia-like aroma when cut into cubes. Ammonia is a naturally occurring by-product of the aging process in cheeses.

:eight: Is ammonia a bleach?

Bleach is considered a potent oxidizing agent whilst ammonia is considered a weak base. There is just one nitrogen atom in ammonia, and three hydrogen atoms make it up. Water, caustic soda, and chlorine are used to make bleach. Unlike bleach, which is known to fade materials, ammonia does not.

:nine: How might I be exposed to ammonia?

Everyone is exposed to modest quantities of ammonia in the environment at some time in their lives. Cleaning items containing ammonia or living near farms where fertilizers are used might expose you to greater quantities of ammonia. If a person spends a lot of time in an enclosed building with a lot of animals, they may be exposed to greater amounts of ammonia.

:keycap_ten: How can ammonia exposure affect my health?

Humans exposed to usual levels of ammonia in the environment have not shown any health impacts. Ammonia in the air can irritate skin, eyes, throats, and lungs as well as coughing and burns in those who are exposed to it at high levels of air.

:closed_book: Conclsuion

The industrial production of ammonia (NH3) is a major source of revenue for any country. It is a naturally occurring substance that may be found in individuals and the environment, as well as in manufacturing and trade. The synthesis of amino acids and nucleotides begins with the use of ammonia, which is a precursor to this process. An important element of the nitrogen cycle, ammonia is generated by microorganisms in the soil. Animal and plant wastes are other sources of natural ammonia because of decomposition.

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