Anhydrous substances

Evaporated milk is a Hquid product obtained by the partial removal of water only from milk. It has a minimum milk-fat content of 7.5 mol % and a minimum milk-solids content of 25.0 mol %. Evaporated skimmed milk is a Hquid product obtained by the partial removal of water only from skimmed milk. It has a minimum milk-solids content of 20.0 mol %. Sweetened condensed milk is a product obtained by the partial removal of water only from milk with the addition of sugars. It has a minimum milk-fat content of 8.0 mol % and a minimum milk-solids content of 28.0 mol %. Skimmed sweetened condensed milk is a product obtained by the partial removal of water only from skimmed milk with the addition of sugars. It has a minimum milk-solids content of 24.0 mol %. AH may contain food additives (qv) as stabilizers, in maximum amounts, including sodium, potassium, and calcium salts of hydrochloric acid at 2000 mg/kg singly citric acid, carbonic acid, orthophosphoric acid, and polyphosphoric acid at 3000 mg/kg in combination, expressed as anhydrous substances and in the evaporated milk carrageenin may be added at 150 mg/kg. 

Afanh molecular mass of anhydrous substance, kgkmoP ... 

The spectra of an organic compound in various solvents differ only in small detail so long as no serious interaction takes place between solute and solvent. Thus the spectrum of a substance in an aprotic solvent (e.g. cyclohexane) should be almost the same as that in water. When addition of water occurs across a C=N bond, the spectrum of the hydrate in water can be vastly different from the spectrum of the anhydrous substance in cyclohexane, and this test has been used on several occasions determine whether or not a neutral species... 

Oxytetracycline occurs as yellow crystals or crystalline powder, has a bitter taste and is odorless. Oxytetracycline hydrochloride should have potency not less than 835 pg C22H24N2O9 per mg [1], whilst for oxytetracycline not less than 832 pg/g [1] or 95.0-102.0% as anhydrous substance [2] or not less than 88.0% of C22H24N2O9 calculated as anhydrous basis [3,4]. For oxytetracycline calcium, it should contain not less than 90.0% and not more than 100.5% [2], or 865 pg C22H24N2O9 per mg [1]. Oxytetracycline was produced by the growth of certain strain of Streptomyces rimosus or obtained by other means. 

Inulin crystallizes in the form of doubly refracting sphero-crystals, the crystalline structure of which is indicated by x-ray patterns.6,4 In aqueous solution inulin has a specific rotation [ajo20 = — 39 to — 40° referred to the anhydrous substance. 

Any product dissolved in an organic solvent is usually treated with an anhydrous salt such as anhydrous magnesium sulfate. Any water remaining in the organic solvent Is absorbed by the anhydrous substance, which can then be removed by vacuum or gravity filtration. 

The amount in grams of o powder required to make 5 L of on aqueous solution at a concentration of 2% w/v of the anhydrous substance... 

According to Hughes, Gilbert et al. the heat of combustion of the anhydrous substance (liquid) is —AHC—148.6 kcal/mole. 

After WWI other European countries, than Germany, and also US started to use azeotropic distn in prepn of abs ethanol, as well as of some other anhydrous substances (such as abs AcOH) and by the middle thirties the method became well established... 

At the ordinary temperature sulphur trioxide forms dense fumes in moist air, caused by the formation of sulphuric acid. The anhydrous substance possesses no acidic properties, but combines violently with water, producing pyrosulphuric and then sulphuric aeid, the heat evolution with a large excess of water amounting to 40-3 Calories per gram-molecule of S03.3 The heats of dilution (II) for one gram-molecule of SO3 with n molecules of H20 are as follows 4... 

Bromotantalum Bromide or tantalum dibromide.—The anhydrous substance is unknown. A compound which has the composition (Ta3Bre)Br.3 H20 or TagBr. THaO is obtained by reducing... 

Tantalum Pentoxide, Ta205, is one of the commonest compounds of tantalum. The anhydrous substance is produced by direct oxidation of the metal or by ignition of hydrated tantalum pentoxide, which is obtained by the methods described below. The removal of niobium and other metals has been described when dealing with the extraction of tantalum and niobium from thdr natural ores. 

By acidifying the hydrolysis mixture with sulfuric acid and by fractionating the product, Curtius procured anhydrous hydrazoic as a colorless liquid which boils at 37°. Hydrazoic acid is intensely poisonous and bad smelling. It is easily exploded by flame, by a brisant explosive, or by contact with metallic mercury. The anhydrous substance is extremely dangerous to handle, but dilute solutions have been distilled without accident. 

Omeprazole sodium contains not less than 98% and not more than the equivalent of 101% of sodium 5-methoxy-2[(RS)-[(4-methoxy-3,5-dimethylpyridin-2-yl)methyl]sulfinyl]-lH-benzimidazole, calculated with reference to the anhydrous substance. 

Like aluminum chloride this salt is completely hydrolyzed if its solution is evaporated to dryness. Only the hydrated salt can be prepared by the action of hydrobromic acid solution (see preceding preparation) the anhydrous substance is prepared by the direct action of the elements on each other. The action is one of such... 

Lithium thiosulphate, Li2S203.—The trihydrate, Li2S203,3H20, is prepared by the interaction of barium thiosulphate and lithium sulphate in aqueous solution.7 Heating eliminates the water of crystallization, and then decomposes the anhydrous substance into sulphur, sulphate, and sulphide. The salt is very deliquescent. 

The trisulphide in the form of trihydrate was similarly prepared by Bottger as golden-yellow crystals. The anhydrous substance is produced by the interaction of sodium monosulphide and the calculated amount of sulphur in boiling toluene.5 Its melting-point is given by Friedrich 8 as 320° C. Its heat of formation in solution is 106-4 Cal.7... 

In properties potassium monosulphide resembles the sodium salt. The anhydrous substance forms small cubic octahedra, isomorphous with the monosulphide of rubidium, but not with that of caesium.1 At the laboratory temperature its density is 1-805.2 The heat of formation of the solid from its elements is 87-1 Cal.,3 and the heat of solution is 22-7 Cal. In dilute solution it has a strongly alkaline reaction, owing to almost complete hydrolysis to the hydroxide and primary sulphide. 

White silky crystals. M.p. 170° to 171°. The anhydrous substance melts at about 138° and is very hygroscopic. 

This table shows the amount of anhydrous substance that is soluble in 100 g of water at the temperature in degrees Celsius as indicated when the name is followed by f, the value is expressed in grams of substance in 100 cm of saturated solution. Solid phase gives the hydrated form in equilibrium with the saturated solution. 

Alcohol of Crystallization.—One more reaction or property of alcohol which shows its similarity to water and which might, indeed, be much more conclusive if we understood more thoroughly the way water itself acts, is that alcohol like water forms crystalline compounds with certain anhydrous substances. In case of water we term it water of crystallizationj so we may call its analogue alcohol of crystallization. Calcium chloride, CaCh, forms crystals containing alcohol of crystallization. 

For partial hydrolysis of the amorphous glycosides, a mixture of 10 g. of glycosides obtained as above, 5 g. of crude enzyme and 700 cc. of water is allowed to stand at pH 5.6 at 37 for nine days. The mixture is treated with 5 volumes of alcohol, filtered through kieselguhr, and concentrated to a small volume under reduced pressure. The residue is extracted with chloroform. The chloroform-soluble glycosides (4.3 g.) are crystallized from methanol, yielding a first crop (2.1 g.) of a mixture of glycosides and crude emicymarin (0.55 g.) from the mother liquors. After repeated crystallization from methanol, emicymarin forms rosettes of stout needles which sinter at 160 and melt at about 207 . The value of Qalo for the anhydrous substance is - -12.8 (c. 2.5, absolute alcohol). 

Commercially available sodium borate decahydrate is usually present as monoclinic prismatic crystals that become opaque on the surface in dry air. In addition to the decahydrate, a pentahydrate exists this is also known as jeweller s borax. The anhydrous substance is also available and is called pyroborax. The EINECS number for sodium borate is 271-536-2. 

Pharmacopoeial content requirements, with reference to the anhydrous substances, are ... 

Degradation products are limited to 9.0% maximum and the total of assay, degradation products, ethylhexanoic acid and sodium chloride to 95.0% minimum with reference to the anhydrous substance. 

Triprolidine Hydrochloride is (E)-2-(3-pyrrolidin-l-yl-l-p-tolylprop 1-enyl)-pyridine hydrochloride monophydrate. It contains not less than 98.5% and not more that 101.0% of Ci9H22N2,HC1, calculated with reference to the anhydrous substance. 

The specific rotation in a 5 (w/v) aqueous solution was [a]jp + 129° 1 5° calcu- g lated with reference to the anhydrous substance ... 

Aloin [10-glucopyranosyl-l,8-dihydroxy-3-(hydroxymethyl)-9(10 f)anthracenone, Barbal-oin] [8015-61-0, 5133-19-7, 1415-73-2] M 418.4, m 148-148.5 , 148-150 . Aloin forms the monohydrate as lemon yellow crystals on crystallisation from H2O (450g/1.5L) which has a lower m 70-80° than the anhydrous substance. [Cahn Simonsen J Chem Soc 2573 1932, Hay Haynes J Chem Soc 3141... 

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