Sodium ammonium

Tartaric acid is noteworthy for a) the excellent way in which the majority of its salts Crystallise, and h) the frequent occurrence of salts having mixed cations. Examples of the latter are sodium potassium tartrate (or Rochelle salt), C4H40 NaK, used for the preparation of Fehling s solution (p. 525), sodium ammonium tartrate, C4H OaNaNH4, used by Pasteur for his early optical resolution experiments, and potassium antimonyl tartrate (or Tartar Emetic), C4H404K(Sb0). The latter is prepared by boiling a solution of potassium hydrogen tartrate (or cream of tartar ) with antimony trioxide,... 

Occasionally an optically inactive sample of tartaric acid was obtained Pasteur noticed that the sodium ammonium salt of optically inactive tartaric acid was a mixture of two mirror image crystal forms With microscope and tweezers Pasteur carefully sep arated the two He found that one kind of crystal (m aqueous solution) was dextrorota tory whereas the mirror image crystals rotated the plane of polarized light an equal amount but were levorotatory... 

The most widely used alkyl sulfate in shampoo preparation is lauryl sulfate. The alkyl component of this sulfate ranges from C-10 to C-18 with a predominance of the C-12 (lauryl) component. By distillation of the fatty alcohol, certain cuts can be obtained which offer the best effects in foaming, cleansing, and rinsing properties for the alkyl sulfate preparation. The range which appears to be most desirable is between C-12 and C-16. Lauryl sulfate detergents are available in various salt forms with the sodium, ammonium, and triethanolamine types being used most frequently in shampoos. 

Arsenic Peroxides. Arsenic peroxides have not been isolated however, elemental arsenic, and a great variety of arsenic compounds, have been found to be effective catalysts ia the epoxidation of olefins by aqueous hydrogen peroxide. Transient peroxoarsenic compounds are beheved to be iavolved ia these systems. Compounds that act as effective epoxidation catalysts iaclude arsenic trioxide, arsenic pentoxide, arsenious acid, arsenic acid, arsenic trichloride, arsenic oxychloride, triphenyl arsiae, phenylarsonic acid, and the arsenates of sodium, ammonium, and bismuth (56). To avoid having to dispose of the toxic residues of these reactions, the arsenic can be immobi1i2ed on a polystyrene resia (57). 

SODIUM AMMONIUM VANADATE SODIUM ARSAHILATE SODIUM ARSENATE SODIUM ARSENITE... 

The optical activity of quartz and certain other materials was first discovered by Jean-Baptiste Biot in 1815 in France, and in 1848 a young chemist in Paris named Louis Pasteur made a related and remarkable discovery. Pasteur noticed that preparations of optically inactive sodium ammonium tartrate contained two visibly different kinds of crystals that were mirror images of each other. Pasteur carefully separated the two types of crystals, dissolved them each in water, and found that each solution was optically active. Even more intriguing, the specific rotations of these two solutions were equal in magnitude and of opposite sign. Because these differences in optical rotation were apparent properties of the dissolved molecules, Pasteur eventually proposed that the molecules themselves were mirror images of each other, just like their respective crystals. Based on this and other related evidence, in 1847 van t Hoff and LeBel proposed the tetrahedral arrangement of valence bonds to carbon. 

L. Pasteur (aged 26) began work on optically active sodium ammonium tartrate. 

Phethenylate sodium Ammonium chloride Cyclofenil Methionine Ammonium sulfate Aminobenzoic acid Fibrinolysin Ammonium sulfamate Cyclamate calcium Ammonium thiocyanate Acetazolamide Clonidine HCl Tolonidine nitrate 2oxazo lamina d-Amphetamine Tanphetamin Ampicillin Mezlocillin Talampicillin... 

Sodium/ammonium None 1-2 (spray) Very light 0-22- 0-65... 

Little was done after Biot s discovery of optical activity until 1848, when Louis Pasteur began work on a study of crystalline tartaric acid salts derived from wine. On crystallizing a concentrated solution of sodium ammonium tartrate below... 

Figure 9.6 Drawings of sodium ammonium tartrate crystals taken from Pasteur s original sketches. One of the crystals is "right-handed" and one is "left-handed."...

Modification of the burning rates, pressure exponents, and temp coefficients of burning rate of the fluorocarbon composites has been accomplished with copper, lead, tin, sodium, ammonium and potassium fluoborates sodium, potassium, lithium, lead, copper and calcium fluorides potassium and ammonium dichromate lead and zinc stearate cesium carbonate potassium and ammonium sulfate copper chromite oxides of magnesium, copper and manganese boron zinc dust and carbon black (Ref 75)... 

Among the large amount of data based on different animals some studies are worth mentioning. Brown and Muir [367] studied alcohol sulfates based on coconut alcohol and on Dobanol 23, neutralized with sodium, ammonium, monoethanolamine, and triethanolamine. The study was carried out by occlusive patch tests on albino rabbits and open patch tests on albino rabbits and albino guinea pigs. Solutions at 0.1 % concentration did not cause any reaction... 

The effect of the nature of the cation, such as sodium, ammonium, magnesium, and alkanolamines, was studied by Fischer [424] and seems to be negligible. 

Ever since Pasteur s work with enantiomers of sodium ammonium tartrate, the interaction of polarized light has provided a powerful, physical probe of molecular chirality [18]. What we may consider to be conventional circular dichroism (CD) arises from the different absorption of left- and right-circularly polarized light by target molecules of a specific handedness [19, 20]. However, absorption measurements made with randomly oriented samples provide a dichroism difference signal that is typically rather small. The chirally induced asymmetry or dichroism can be expressed as a Kuhn g-factor [21] defined as ... 

Trinitrophenol can only be stored safely in the form of a paste with water. Lead, mercury, copper, zinc, iron and nickel salts are sensitive to impact, friction and heat. Sodium, ammonium and amine salts give rise to explosions. When it was poured on to a cement floor, trinitrophenol formed a calcium salt that detonated when it came into contact with shoes. Trinitrophenol salts in the form of moist paste are stable. Aluminium salt is not explosive, but combusts spontaneously when in contact with water. 

Sodium ammonium hydrogenphosphate Ammonium hydrogensulphride Anunonium sdlphamate Hydrazine sulphate Ammonium phosphate Diammonium sulphite Ammonium thiosulphate Ammonium molybdate Amnwnium sulphate Diammonium peroxodlsutphate... 

Potentiometry is the measurement of the potential at an electrode or membrane electrode, so the detector response is in units of volts. The potentio-metric response tends to be slow, so potentiometry is used infrequently in analysis.47 One example is the use of a polymeric membrane impregnated with ionophores for the selective detection of potassium, sodium, ammonium, and calcium 48 In process chromatography, potentiometry may be used to monitor selected ions or pH as these values change over the course of the gradient. 

A young Louis Pasteur observed that many salts of tartaric acid formed chiral crystals (which he knew was related to their ability to rotate the plane of polarization of plane-polarized light). He succeeded in solving the mystery of racemic acid when he found that the sodium ammonium salt of racemic acid could be crystallized to produce a crystal conglomerate. After physical separation of the macroscopic enantiomers with a dissecting needle, Pasteur... 

The method is applicable to only solid substances which form well defined crystals. Thus in 1848 Pasteur separated for the first time the active forms of sodium ammonium tartate by evaporating a recemic solution below 27°. Two type of crystals were obtained, which had different shapes and were the mirror images of each other. The crystals were separated under a microscope with the help of forceps. Since the crystals of one type were all d isomer and the crystals of the other type were 1 isomer, their separation led to a separation of the recemic mixture. On dissolving in solution they showed opposite rotation. 

The manual separation of the enantiomorphous crystals of sodium ammonium tartrate tetrahydrate (Figure 1) by Pasteur in 1848 (1) is historically significant, because it laid the foundations of modem stereochemistry. This experiment demonstrated for the first time that certain classes of molecules display enan-tiomorphism even when dissolved in solvent. These observations eventually paved the way for the inspired suggestion, made more than two decades later, by van t Hoff (2) and Le Bel (3), of a tetrahedral arrangement of bonds around the carbon atom. 

Figure I. Enantiomorphous crystals of sodium ammonium tartrate -4H20.

Crystals composed of the R and S enantiomers of the same racemic mixture must be related by mirror symmetry in terms of both their internal structure and external shape. Enantiomorphous crystals may be sorted visually only if the crystals develop recognizable hemihedral faces. [Opposite (hid) and (hkl) crystal faces are hemihedral if their surface structures are not related to each other by symmetry other than translation, in which case the crystal structure is polar along a vector joining the two faces. Under such circumstances the hemihedral (hkl) and (hkl) faces may not be morphologically equivalent.] It is well known that Pasteur s discovery of enantiomorphism through die asymmetric shape of die crystals of racemic sodium ammonium tartrate was due in part to a confluence of favorable circumstances. In the cold climate of Paris, Pasteur obtained crystals in the form of conglomerates. These crystals were large and exhibited easily seen hemihedral faces. In contrast, at temperatures above 27°C sodium ammonium tartrate forms a racemic compound. 

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