Liquid ammonia physical properties

W. L. Jolly and C. J. Hallada, Liquid ammonia. Chap. 1 in T. C. WaDDINGTON (ed.), Non-aqueous Solvent Systems, pp. 1-45, Academic Press, London, 1965. J. C. Thompson, The physical properties of metal solutions in non-aqueous solvents. Chap. 6 in J. Lagowski (ed.). The Chemistry of Non-aqueous Solvents, Vol. 2, pp. 265-317, Academic Press, New York, 1967. J. Jander (ed.). Chemistry in Anhydrous Liquid Ammonia, Wiley, Interscience, New York, 1966, 561 pp. 

Ammonia is a pungent, toxic gas that condenses to a colorless liquid at — 33°C. The liquid resembles water in its physical properties, including its ability to act as a solvent for a wide range of substances. Because the dipole moment of the NH3 molecule (1.47 D) is lower than that of the H20 molecule (1.85 D), salts with strong ionic character, such as KCI, cannot dissolve in ammonia. Salts with polarizable anions tend to be more soluble in ammonia than are salts with greater ionic character. For example, iodides are more soluble than chlorides in ammonia. Liquid ammonia undergoes much less autoprotolysis than water ... 

Constitution XV for sucrose has up to the present satisfied all demands made upon it. Like its precursors, I and II (page 6), it was not incompatible with physical properties of sucrose such as the magnetic rotation, or the parachor, although the latter claim has been denied. Von Lippmann lists a great many early determinations of the physical properties of the sugar more recent measurements include the heat of combustion, the molecular weight in liquid ammonia, and various optical and electrical constants. ... 

The C-perfluorodisulfonimide (72) is readily N-fluorinated (Equation (4)) by liquid fluorine <87JA7194, 87JAP8726264>. The N-fluoro derivative (73) is a powerful fluorinating agent of high stability and suitable physical properties. It can be converted back to the imide (72) by ammonia... 

Physical properties of the solvent are used to describe polarity scales. These include both bulk properties, such as dielectric constant (relative permittivity), refractive index, latent heat of fusion, and vaporization, and molecular properties, such as dipole moment. A second set of polarity assessments has used measures of the chemical interactions between solvents and convenient reference solutes (see table 3.2). Polarity is a subjective phenomenon. (To a synthetic organic chemist, dichloromethane may be a polar solvent, whereas to an inorganic chemist, who is used to water, liquid ammonia, and concentrated sulfuric acid, dichloromethane has low polarity.)... 

Physical Properties. Ammonium thiocyanate [1762-95-4], NH4SCN, is a hygroscopic crystalline solid which deliquesces at high humidities (375,376). It melts at 149°C with partial isomerization to thiourea. It is soluble in water to the extent of 65 wt % at 25°C and 77 wt % at 60°C. It is also soluble to 35 wt % in methanol and 20 wt % in ethanol at 25°C. It is highly soluble in liquid ammonia and liquid sulfur dioxide, and moderately soluble in acetonitrile. 

Ethyleneimine (El) and its two most important derivaiives. 2-methyla/iri-dine (propyleneintinei. ami I, (2-hydroxyeihyl)aziridinc (HEA) are colorless liquids. They are miscible in all proportions with water and ihe majority of organic solvents. Ethyleneimine is not miscible with concenlrated aqueous NaOH solutions ( > 17(F by weight). Ethyleneimine has an odor similar to ammonia. The physical properties of ethyleneimine and the derivaiives mentioned are given in Table I. 

Physical Properties. o -Aminomtriles are stable at modest temperatures (<70°C in the absence of water in the presence of water, they can degrade to their original constituents, i.e., ketone (aldehyde), ammonia and hydrogen cyanide if insufficient ammonia is present. The aminoiiilriles based on ketones are clear colorless liquids, but sometimes appear yellow to brown depending on the synthetic procedure and the amount of decomposition. They are soluble in polar organic solvents and in aromatic solvents. 

Some of the physical properties of fatty acid nitriles are listed in Table 14 (see also Carboxylic acids). Fatty acid nitriles are produced as intermediates for a large variety of amines and amides. Estimated U.S. production capacity (1980) was >140,000 t/yr. Fatty acid nitriles are produced from the corresponding acids by a catalytic reaction with ammonia in the liquid phase. They have little use other than as intermediates but could have some utility as surfactants (qv), mst inhibitors, and plasticizers (qv). 

We can also compare the rate of hydrogen exchange in liquid ammonia and in anhydrous hydrazine, ethylenediamine, and ethanolamine. Some physical properties of these solvents are given below (/jl = dipole moment). 

The physical properties of these intriguing systems have been studied in serious vein since the 1920s (111,164). At the present time, this interest continues unabated. In its more recent development, the multidisciplinary nature of metal-solution investigations has also spilled over into the wider fields of excess electrons in disordered media (38, 39, 99, 103). The recent Colloque Weyl V conference on metal-ammonia solutions and excess electrons in liquids (39) brought together almost 200 scientists from all disciplines. The present review... 

Liquid ammonia has been suggested as a solvent for the C4 separation(l). A drawback to its use in the liquid state, however, is the need for costly refrigeration. Its use as a supercritical solvent would also be acceptable were it not for its high critical temperature (405.45 K). High temperature favors the polymerization of the butadiene hence, its limitation in this role. In this study, a method was developed that seeks to circumvent this problem and yet achieve the desired separation of the C4 s. Prausnitz(2) discusses the use of a mixture of supercritical solvents whose properties provide the optimal physical conditions for efficient extraction. It is equally possible to prepare mixtures of solvents that not only modify those critical properties of the individual solvent component, but also introduce the chemical features needed to maximize the separation of the feed mixture. 

Methylamines are colorless liquids that are volatile at normal atmospheric conditions. They have threshold odor limits of less than 10 ppm, and at low concentrations they have a fishy smell. At high concentrations they smell like ammonia. The physical properties are given in Table 14.1 and Table 14.2. 

You can easily block in liquid-full chemical process piping with no vapor space for expansion. Many fluids, including liquid ammonia, liquid chlorine, liquid propane, liquid vinyl chloride, and benzene, if improperly isolated, can develop hundreds of pounds per square inch (many atmospheres) of pressure with fluctuation in nighttime and daytime temperatures. The liquid tries to expand as a result of its physical properties, but it is prevented by... 

As a general rule, organic compounds are usually more soluble in liquid ammonia than they are in water. Inorganic salts are usually more soluble in water unless the cation forms stable complexes with NH3. For example, AgCl is more soluble in liquid ammonia than it is in water because of the stability of Ag(NH3)2+. Because the basic species in liquid NH3 is NH2, reactions that involve strongly basic materials can frequently be carried out in liquid NH3 more readily than they can in water because NH2 is a stronger base than OH-. Some of the important physical properties of liquid NH3 are shown in Table 5.5. 

Although no attempt will be made to describe the chemistry of all of the nonaqueous solvents listed in Table 5.4, the survey to this point has included ammonia as a basic solvent and liquid hydrogen fluoride as an acidic solvent. Another solvent that has been extensively utilized in both inorganic and organic chemistry is sulfur dioxide. Accordingly, we will give a brief survey of the chemistry of liquid sulfur dioxide for which the physical properties are presented in Table 5.8. 

White Cd(CN)2 is sparingly soluble in water, except in the presence of CN ions, owing to the formation of soluble anionic complexes. On heating it darkens and decomposes at about 200 °C. Cd(CN)2, like Zn(CN)2, has a cubic anti-cuprite structure. Colorless cadmium thiocyanate is sparingly soluble in water, ethanol, and liquid ammonia. In the solid, Cd + is surrounded by an N2S4 octahedron. Cadmium thiocyanate polymers exhibit highly anisotropic physical properties. Yellow Cd(N3)2 is prepared by mixing solutions of Cd(N03)2 and NaNs. The crystals are orthorhombic and decompose with detonation when heated. Cadmium pseudohalides (see Pseudohalide) may be prepared by metathesis (equation 3). 

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