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53-497: Ethylenediamine is produced industrially by treating 1,2-dichloroethane with ammonia under pressure at 180 °C in an aqueous medium: In this reaction hydrogen chloride is generated, which forms a salt with the amine. The amine is liberated by addition of sodium hydroxide and can then be recovered by rectification  [ de ] . Diethylenetriamine (DETA) and triethylenetetramine (TETA) are formed as by-products. Another industrial route to ethylenediamine involves

106-513: A base , a proton acceptor. Ammonia is moderately basic; a 1.0  M aqueous solution has a pH of 11.6, and if a strong acid is added to such a solution until the solution is neutral ( pH = 7 ), 99.4% of the ammonia molecules are protonated . Temperature and salinity also affect the proportion of ammonium [NH 4 ] . The latter has the shape of a regular tetrahedron and is isoelectronic with methane . The ammonia molecule readily undergoes nitrogen inversion at room temperature;

159-484: A vapour pressure of less than 1 bar even at 25 °C (77 °F). However, few oxyanion salts with other cations dissolve. Liquid ammonia will dissolve all of the alkali metals and other electropositive metals such as Ca , Sr , Ba , Eu and Yb (also Mg using an electrolytic process ). At low concentrations (<0.06 mol/L), deep blue solutions are formed: these contain metal cations and solvated electrons , free electrons that are surrounded by

212-444: A cage of ammonia molecules. These solutions are strong reducing agents. At higher concentrations, the solutions are metallic in appearance and in electrical conductivity. At low temperatures, the two types of solution can coexist as immiscible phases. The range of thermodynamic stability of liquid ammonia solutions is very narrow, as the potential for oxidation to dinitrogen, E ° ( N 2 + 6 [NH 4 ] + 6 e ⇌ 8 NH 3 ),

265-415: A cloud of ammonium chloride , which seems to appear 'out of nothing' as the salt aerosol forms where the two diffusing clouds of reagents meet between the two bottles. The salts produced by the action of ammonia on acids are known as the ammonium salts and all contain the ammonium ion ( [NH 4 ] ). Although ammonia is well known as a weak base, it can also act as an extremely weak acid. It

318-550: A colourless liquid , which boils at −33.1 °C (−27.58 °F), and freezes to colourless crystals at −77.7 °C (−107.86 °F). Little data is available at very high temperatures and pressures, but the liquid-vapor critical point occurs at 405 K and 11.35 MPa. The crystal symmetry is cubic, Pearson symbol cP16, space group P2 1 3 No.198, lattice constant 0.5125  nm . Liquid ammonia possesses strong ionising powers reflecting its high ε of 22 at −35 °C (−31 °F). Liquid ammonia has

371-406: A far lower temperature than would be possible with water alone. Substances containing ammonia, or those that are similar to it, are called ammoniacal . Ammonia is a colourless gas with a characteristically pungent smell . It is lighter than air , its density being 0.589 times that of air . It is easily liquefied due to the strong hydrogen bonding between molecules. Gaseous ammonia turns to

424-407: A fuel for thermal power production. The flammable range of ammonia in dry air is 15.15–27.35% and in 100% relative humidity air is 15.95–26.55%. For studying the kinetics of ammonia combustion, knowledge of a detailed reliable reaction mechanism is required, but this has been challenging to obtain. Ammonia is a direct or indirect precursor to most manufactured nitrogen-containing compounds . It

477-452: A laboratorial setting, gaseous ammonia can be detected by using concentrated hydrochloric acid or gaseous hydrogen chloride. A dense white fume (which is ammonium chloride vapor) arises from the reaction between ammonia and HCl(g). Ammoniacal nitrogen (NH 3 –N) is a measure commonly used for testing the quantity of ammonium ions, derived naturally from ammonia, and returned to ammonia via organic processes, in water or waste liquids. It

530-432: A pale yellowish-green flame. Ignition occurs when chlorine is passed into ammonia, forming nitrogen and hydrogen chloride ; if chlorine is present in excess, then the highly explosive nitrogen trichloride ( NCl 3 ) is also formed. The combustion of ammonia to form nitrogen and water is exothermic : The standard enthalpy change of combustion , Δ H ° c , expressed per mole of ammonia and with condensation of

583-790: A pharmaceutical excipient, after oral administration its bioavailability is about 0.34, due to a substantial first-pass effect . Less than 20% is eliminated by renal excretion. Ethylenediamine-derived antihistamines are the oldest of the five classes of first-generation antihistamines , beginning with piperoxan aka benodain, discovered in 1933 at the Pasteur Institute in France, and also including mepyramine , tripelennamine , and antazoline . The other classes are derivatives of ethanolamine, alkylamine , piperazine , and others (primarily tricyclic and tetracyclic compounds related to phenothiazines , tricyclic antidepressants , as well as

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636-593: A pressure of one atmosphere , but the liquid can often be handled in the laboratory without external cooling. Household ammonia or ammonium hydroxide is a solution of ammonia in water. Pliny , in Book XXXI of his Natural History , refers to a salt named hammoniacum , so called because of the proximity of its source to the Temple of Jupiter Amun ( Greek Ἄμμων Ammon ) in the Roman province of Cyrenaica . However,

689-559: A total of eight electrons, or four electron pairs that are arranged tetrahedrally . Three of these electron pairs are used as bond pairs, which leaves one lone pair of electrons. The lone pair repels more strongly than bond pairs; therefore, the bond angle is not 109.5°, as expected for a regular tetrahedral arrangement, but 106.8°. This shape gives the molecule a dipole moment and makes it polar . The molecule's polarity, and especially its ability to form hydrogen bonds , makes ammonia highly miscible with water. The lone pair makes ammonia

742-438: A useful analogy is an umbrella turning itself inside out in a strong wind. The energy barrier to this inversion is 24.7 kJ/mol, and the resonance frequency is 23.79  GHz , corresponding to microwave radiation of a wavelength of 1.260 cm. The absorption at this frequency was the first microwave spectrum to be observed and was used in the first maser . One of the most characteristic properties of ammonia

795-465: A very high standard enthalpy change of vapourization (23.5  kJ/mol ; for comparison, water 's is 40.65 kJ/mol, methane 8.19 kJ/mol and phosphine 14.6 kJ/mol) and can be transported in pressurized or refrigerated vessels; however, at standard temperature and pressure liquid anhydrous ammonia will vaporize. Ammonia readily dissolves in water. In an aqueous solution, it can be expelled by boiling. The aqueous solution of ammonia

848-497: Is basic , and may be described as aqueous ammonia or ammonium hydroxide . The maximum concentration of ammonia in water (a saturated solution ) has a specific gravity of 0.880 and is often known as '.880 ammonia'. Liquid ammonia is a widely studied nonaqueous ionising solvent. Its most conspicuous property is its ability to dissolve alkali metals to form highly coloured, electrically conductive solutions containing solvated electrons . Apart from these remarkable solutions, much of

901-814: Is a protic substance and is capable of formation of amides (which contain the NH − 2 ion). For example, lithium dissolves in liquid ammonia to give a blue solution ( solvated electron ) of lithium amide : Like water, liquid ammonia undergoes molecular autoionisation to form its acid and base conjugates : Ammonia often functions as a weak base , so it has some buffering ability. Shifts in pH will cause more or fewer ammonium cations ( NH + 4 ) and amide anions ( NH − 2 ) to be present in solution . At standard pressure and temperature, Ammonia does not burn readily or sustain combustion , except under narrow fuel-to-air mixtures of 15–28% ammonia by volume in air. When mixed with oxygen , it burns with

954-474: Is a commercially significant mold- release agent and a surfactant in gasoline and motor oil. Ethylenediamine is a well-known bidentate chelating ligand for coordination compounds , with the two nitrogen atoms donating their lone pairs of electrons when ethylenediamine acts as a ligand. It is often abbreviated "en" in inorganic chemistry. The complex [Co(en) 3 ] is a well studied example. Schiff base ligands easily form from ethylenediamine. For example,

1007-402: Is a measure used mainly for quantifying values in waste treatment and water purification systems, as well as a measure of the health of natural and man-made water reserves. It is measured in units of mg/L ( milligram per litre ). The ancient Greek historian Herodotus mentioned that there were outcrops of salt in an area of Libya that was inhabited by a people called the 'Ammonians' (now

1060-430: Is a skin and respiratory irritant. Unless tightly contained, liquid ethylenediamine will release toxic and irritating vapors into its surroundings, especially on heating. The vapors absorb moisture from humid air to form a characteristic white mist, which is extremely irritating to skin, eyes, lungs and mucous membranes. [REDACTED] Media related to Ethylenediamine at Wikimedia Commons Ammonia Ammonia

1113-568: Is about 10 . Liquid ammonia is an ionising solvent, although less so than water, and dissolves a range of ionic compounds, including many nitrates , nitrites , cyanides , thiocyanates , metal cyclopentadienyl complexes and metal bis(trimethylsilyl)amides . Most ammonium salts are soluble and act as acids in liquid ammonia solutions. The solubility of halide salts increases from fluoride to iodide . A saturated solution of ammonium nitrate ( Divers' solution , named after Edward Divers ) contains 0.83 mol solute per mole of ammonia and has

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1166-454: Is an inorganic chemical compound of nitrogen and hydrogen with the formula N H 3 . A stable binary hydride and the simplest pnictogen hydride , ammonia is a colourless gas with a distinctive pungent smell. Biologically, it is a common nitrogenous waste , and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to fertilisers . Around 70% of ammonia produced industrially

1219-548: Is an organic compound with the formula (CH 3 C(O)) 2 NCH 2 CH 2 N(C(O)CH 3 ) 2 . This white solid is commonly used as a bleach activator in laundry detergents and for paper pulp. It is produced by acetylation of ethylenediamine . TAED is an important component of laundry detergents that use "active oxygen" bleaching agents. Active oxygen bleaching agents include sodium perborate , sodium percarbonate , sodium perphosphate, sodium persulfate , and urea peroxide . These compounds release hydrogen peroxide during

1272-437: Is an irritant and irritation increases with concentration; the permissible exposure limit is 25  ppm , and lethal above 500 ppm by volume. Higher concentrations are hardly detected by conventional detectors, the type of detector is chosen according to the sensitivity required (e.g. semiconductor, catalytic, electrochemical). Holographic sensors have been proposed for detecting concentrations up to 12.5% in volume. In

1325-416: Is an unproductive pathway. TAED is prepared in a two-stage process from ethylenediamine and acetic anhydride. The process is nearly quantitative. Powdered TAED is stabilized by granulation with the aid of the sodium salt of carboxymethylcellulose (Na-CMC), which are sometimes additionally coated blue or green. Despite the relatively low solubility of TAED in cool water, (1 g/L at 20 °C),

1378-403: Is formed. Pentavalent ammonia is known as λ -amine, nitrogen pentahydride decomposes spontaneously into trivalent ammonia (λ -amine) and hydrogen gas at normal conditions. This substance was once investigated as a possible solid rocket fuel in 1966. Ammonia is also used to make the following compounds: Ammonia is a ligand forming metal ammine complexes . For historical reasons, ammonia

1431-508: Is found throughout the Solar System on Mars , Jupiter , Saturn , Uranus , Neptune , and Pluto , among other places: on smaller, icy bodies such as Pluto, ammonia can act as a geologically important antifreeze, as a mixture of water and ammonia can have a melting point as low as −100 °C (−148 °F; 173 K) if the ammonia concentration is high enough and thus allow such bodies to retain internal oceans and active geology at

1484-587: Is generated via the Ostwald process by oxidation of ammonia with air over a platinum catalyst at 700–850 °C (1,292–1,562 °F), ≈9 atm. Nitric oxide and nitrogen dioxide are intermediate in this conversion: Nitric acid is used for the production of fertilisers , explosives , and many organonitrogen compounds. The hydrogen in ammonia is susceptible to replacement by a myriad substituents. Ammonia gas reacts with metallic sodium to give sodamide , NaNH 2 . With chlorine, monochloramine

1537-519: Is its basicity . Ammonia is considered to be a weak base. It combines with acids to form ammonium salts ; thus, with hydrochloric acid it forms ammonium chloride (sal ammoniac); with nitric acid , ammonium nitrate , etc. Perfectly dry ammonia gas will not combine with perfectly dry hydrogen chloride gas; moisture is necessary to bring about the reaction. As a demonstration experiment under air with ambient moisture, opened bottles of concentrated ammonia and hydrochloric acid solutions produce

1590-440: Is named ammine in the nomenclature of coordination compounds . One notable ammine complex is cisplatin ( Pt(NH 3 ) 2 Cl 2 , a widely used anticancer drug. Ammine complexes of chromium (III) formed the basis of Alfred Werner 's revolutionary theory on the structure of coordination compounds. Werner noted only two isomers ( fac - and mer -) of the complex [CrCl 3 (NH 3 ) 3 ] could be formed, and concluded

1643-609: Is not known whether the term is equivalent to the more modern sal ammoniac (ammonium chloride). The fermentation of urine by bacteria produces a solution of ammonia ; hence fermented urine was used in Classical Antiquity to wash cloth and clothing, to remove hair from hides in preparation for tanning, to serve as a mordant in dying cloth, and to remove rust from iron. It was also used by ancient dentists to wash teeth. Tetraacetylethylenediamine Tetraacetylethylenediamine , commonly abbreviated as TAED,

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1696-404: Is only +0.04 V. In practice, both oxidation to dinitrogen and reduction to dihydrogen are slow. This is particularly true of reducing solutions: the solutions of the alkali metals mentioned above are stable for several days, slowly decomposing to the metal amide and dihydrogen. Most studies involving liquid ammonia solutions are done in reducing conditions; although oxidation of liquid ammonia

1749-523: Is produced biologically in a process called nitrogen fixation , but even more is generated industrially by the Haber process . The process helped revolutionize agriculture by providing cheap fertilizers. The global industrial production of ammonia in 2021 was 235 million tonnes. Industrial ammonia is transported by road in tankers , by rail in tank wagons , by sea in gas carriers , or in cylinders . Ammonia boils at −33.34 °C (−28.012 °F) at

1802-463: Is the chelating agent EDTA , which is derived from ethylenediamine via a Strecker synthesis involving cyanide and formaldehyde . Hydroxyethylethylenediamine is another commercially significant chelating agent. Numerous bio-active compounds and drugs contain the N–CH 2 –CH 2 –N linkage, including some antihistamines . Salts of ethylenebisdithiocarbamate are commercially significant fungicides under

1855-578: Is the main bleach activator used in European laundry detergents and has an estimated annual consumption of 75 kt. TAED reacts with alkaline peroxide via the process called perhydrolysis releasing of peracetic acid . The first perhydrolysis gives triacetylethylenediamine (TriAED) and the second gives diacetylethylenediamine (DAED): TAED typically provides only two equivalents of peracetic acid, although four are theoretically possible. Competing with perhydrolysis, TAED also undergoes some hydrolysis , which

1908-543: Is the precursor to nitric acid, which is the source for most N-substituted aromatic compounds. Amines can be formed by the reaction of ammonia with alkyl halides or, more commonly, with alcohols : Its ring-opening reaction with ethylene oxide give ethanolamine , diethanolamine , and triethanolamine . Amides can be prepared by the reaction of ammonia with carboxylic acid and their derivatives. For example, ammonia reacts with formic acid (HCOOH) to yield formamide ( HCONH 2 ) when heated. Acyl chlorides are

1961-433: Is used to make fertilisers in various forms and composition, such as urea and diammonium phosphate . Ammonia in pure form is also applied directly into the soil. Ammonia, either directly or indirectly, is also a building block for the synthesis of many chemicals. Ammonia occurs in nature and has been detected in the interstellar medium. In many countries, it is classified as an extremely hazardous substance . Ammonia

2014-438: Is usually slow, there is still a risk of explosion, particularly if transition metal ions are present as possible catalysts. The ammonia molecule has a trigonal pyramidal shape, as predicted by the valence shell electron pair repulsion theory (VSEPR theory) with an experimentally determined bond angle of 106.7°. The central nitrogen atom has five outer electrons with an additional electron from each hydrogen atom. This gives

2067-461: Is very difficult in the absence of a catalyst (such as platinum gauze or warm chromium(III) oxide ), due to the relatively low heat of combustion , a lower laminar burning velocity, high auto-ignition temperature , high heat of vapourization , and a narrow flammability range . However, recent studies have shown that efficient and stable combustion of ammonia can be achieved using swirl combustors, thereby rekindling research interest in ammonia as

2120-477: The Siwa oasis in northwestern Egypt, where salt lakes still exist). The Greek geographer Strabo also mentioned the salt from this region. However, the ancient authors Dioscorides , Apicius , Arrian , Synesius , and Aëtius of Amida described this salt as forming clear crystals that could be used for cooking and that were essentially rock salt . Hammoniacus sal appears in the writings of Pliny , although it

2173-477: The cyproheptadine - phenindamine family) Ethylenediamine, because it contains two amine groups, is a widely used precursor to various polymers. Condensates derived from formaldehyde are plasticizers. It is widely used in the production of polyurethane fibers. The PAMAM class of dendrimers are derived from ethylenediamine. The bleaching activator tetraacetylethylenediamine is generated from ethylenediamine. The derivative N , N -ethylenebis(stearamide) (EBS)

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2226-443: The addition of Nessler's solution , which gives a distinct yellow colouration in the presence of the slightest trace of ammonia or ammonium salts. The amount of ammonia in ammonium salts can be estimated quantitatively by distillation of the salts with sodium (NaOH) or potassium hydroxide (KOH), the ammonia evolved being absorbed in a known volume of standard sulfuric acid and the excess of acid then determined volumetrically ; or

2279-443: The ammonia may be absorbed in hydrochloric acid and the ammonium chloride so formed precipitated as ammonium hexachloroplatinate , [NH 4 ] 2 [PtCl 6 ] . Sulfur sticks are burnt to detect small leaks in industrial ammonia refrigeration systems. Larger quantities can be detected by warming the salts with a caustic alkali or with quicklime , when the characteristic smell of ammonia will be at once apparent. Ammonia

2332-437: The brand names Maneb , Mancozeb, Zineb , and Metiram. Some imidazoline -containing fungicides are derived from ethylenediamine. Ethylenediamine is an ingredient in the common bronchodilator drug aminophylline , where it serves to solubilize the active ingredient theophylline . Ethylenediamine has also been used in dermatologic preparations, but has been removed from some because of causing contact dermatitis. When used as

2385-490: The chemistry in liquid ammonia can be classified by analogy with related reactions in aqueous solutions . Comparison of the physical properties of NH 3 with those of water shows NH 3 has the lower melting point, boiling point, density, viscosity , dielectric constant and electrical conductivity . These differences are attributed at least in part to the weaker hydrogen bonding in NH 3 . The ionic self- dissociation constant of liquid NH 3 at −50 °C

2438-631: The description Pliny gives of the salt does not conform to the properties of ammonium chloride . According to Herbert Hoover 's commentary in his English translation of Georgius Agricola 's De re metallica , it is likely to have been common sea salt. In any case, that salt ultimately gave ammonia and ammonium compounds their name. Traces of ammonia/ammonium are found in rainwater. Ammonium chloride ( sal ammoniac ), and ammonium sulfate are found in volcanic districts. Crystals of ammonium bicarbonate have been found in Patagonia guano . Ammonia

2491-559: The diamine condenses with 4-Trifluoromethylbenzaldehyde to give to the diimine. The salen ligands , some of which are used in catalysis, are derived from the condensation of salicylaldehydes and ethylenediamine. Related derivatives of ethylenediamine include ethylenediaminetetraacetic acid (EDTA) , tetramethylethylenediamine (TMEDA), and tetraethylethylenediamine (TEEDA). Chiral analogs of ethylenediamine include 1,2-diaminopropane and trans -diaminocyclohexane . Ethylenediamine, like ammonia and other low-molecular weight amines,

2544-428: The granulate dissolves rapidly in the washing liquor. The peroxyacetic acid formed has bactericidal , virucidal and fungicidal properties, thereby enabling TAED with percarbonate to disinfect and deodorize . Triacetylethylenediamine is mostly non-toxic and easily biodegradable. TAED and its byproduct DAED have low aquatic ecotoxicity . Triacetylethylenediamine shows a very low toxicity in all exposure routes,

2597-511: The ligands must be arranged around the metal ion at the vertices of an octahedron . Ammonia forms 1:1 adducts with a variety of Lewis acids such as I 2 , phenol , and Al(CH 3 ) 3 . Ammonia is a hard base (HSAB theory) and its E & C parameters are E B = 2.31 and C B = 2.04. Its relative donor strength toward a series of acids, versus other Lewis bases, can be illustrated by C-B plots . Ammonia and ammonium salts can be readily detected, in very minute traces, by

2650-474: The most reactive, but the ammonia must be present in at least a twofold excess to neutralise the hydrogen chloride formed. Esters and anhydrides also react with ammonia to form amides. Ammonium salts of carboxylic acids can be dehydrated to amides by heating to 150–200 °C as long as no thermally sensitive groups are present. Other organonitrogen compounds include alprazolam , ethanolamine , ethyl carbamate and hexamethylenetetramine . Nitric acid

2703-787: The reaction of ethanolamine and ammonia: This process involves passing the gaseous reactants over a bed of nickel heterogeneous catalysts . It can be produced in the lab by the reaction of ethylene glycol and urea . Ethylenediamine can be purified by treatment with sodium hydroxide to remove water followed by distillation. Ethylenediamine is used in large quantities for production of many industrial chemicals. It forms derivatives with carboxylic acids (including fatty acids ), nitriles , alcohols (at elevated temperatures), alkylating agents, carbon disulfide , and aldehydes and ketones . Because of its bifunctional nature, having two amino groups, it readily forms heterocycles such as imidazolidines . A most prominent derivative of ethylenediamine

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2756-405: The wash cycle, but the release of hydrogen peroxide is low when these compounds are used in temperatures below 45 °C (113 °F). TAED and hydrogen peroxide react to form peroxyacetic acid , a more efficient bleach, allowing lower temperature wash cycles, around 40 °C (104 °F). TAED was first used in a commercial laundry detergent in 1978 ( Skip by Unilever ). Currently, TAED

2809-488: The water formed, is −382.81 kJ/mol. Dinitrogen is the thermodynamic product of combustion : all nitrogen oxides are unstable with respect to N 2 and O 2 , which is the principle behind the catalytic converter . Nitrogen oxides can be formed as kinetic products in the presence of appropriate catalysts , a reaction of great industrial importance in the production of nitric acid : A subsequent reaction leads to NO 2 : The combustion of ammonia in air

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