Physical properties water solubility

Successful development of a commercial-scale solvent-extraction process depends to a large degree on selection of the most appropriate solvent. Important criteria for solvent selection include price, toxicological constraints, availability, solute selectivity, recovery difficulties, physical properties (water solubility, specific gravity, viscosity, boiling point), and operational hazards (flammability, volatility). Final choice would likely be a compromise among these criteria. 

The key feature of ethylene glycol (EG) is the hydroxyl group, -OH, one on each of the two carbon atoms. The hydroxyls are responsible for its reactivity EG is a monomer used in the production of polyester polymers. The hydroxyls also give EG its most important physical property its solubility in water. That, linked with its low freeze point, makes EG suitable as an antifreeze and as a deicer. When EG is sprayed on ice, it combines with the water crystals and lowers the freeze point. This causes the mixture to melt and effectively keeps it in the liquid state. 

The significance of this study goes to the heart of our task. In our discussion of the extraction of pollutants, we suggested that polyglycols had utility as extracting solvents, but because of their physical nature (water solubility) they were not useful. We proposed to polymerize the glycols into water-insoluble polymers by reactions with polyisocyanates. We then presented data to support the notion that the polymers maintained the solvent properties, but they were translated into a water-insoluble matrix (a polyurethane). 

Caprolactam, mol wt 113.16, is a white, hygroscopic, crystalline solid at ambient temperature, with a characteristic odor. It is very soluble in water and in most common organic solvents and is sparingly soluble in high molecular weight aliphatic hydrocarbons. Molten caprolactam is a powerful solvent for polar and nonpolar organic chemicals. Selected physical properties and solubilities of caprolactam are listed in Tables 1 and 2, respectively. 

The mobility and bioavailability of CPs, and thus their bioremediation, are affected by their chemical and physical properties. The solubility of CPs in water decreases as the number of chlorine substituents increases. In addition, the increase in the number of chlorosubstituents in the phenol ring increases the lipophilicity of CPs and thus their tendency to bioaccumulate. The water solubilities, pKa (acidity constant) and pK0W (octanol-water partition constant) values for environmentally important CPs are summarized in Figure 8.1. 

A diverse collection of quantitative property-water solubility relationships (QPWSR) is available in the literature. These QPWSR differ in their solubility representation (Cw, Sw, Xw), spectrum of independent variables, and applicability with respect to structure and physical state (liquid or solid). The following types of QPWSR are considered ... 

Quantitative distributions of organic pollutants in different phases largely depend on their physical properties the solubility constants in water (K, ) and soil (Koc) and Henry s constant. Figure 2.4 illustrates their distribution in these phases. 

This non-polarity also affects another physical property the solubility of alkanes in water. 

The aqueous activity coefficient of a compound describes the effect of molecular structure on aqueous solubility. If a compound mixes with water and forms an ideal solution, then the activity coefficient would be taken as unity and the last term in Eq. (1) would become zero. In such a case, then the solid phase, if any, would be the sole physical property inhibiting solubility. Most drugs are relatively nonpolar and do not form ideal solutions with water. Therefore in order to understand the extent by which the inherent molecular structure is limiting solubility, it is helpful to obtain an estimate for the aqueous activity coefficient. 

Within the two broad classes, proteins are subdivided on the basis of physical properties, especially solubility for example, albumins (soluble in water, coagulated by heat), globulins (insoluble in water, soluble in dilute salt solutions), etc. 

Mackay Level 1 modeling was used to estimate the distribution of 2-butoxyethanol in various environmental compartments (air, soil, water, biota, suspended solids, sediment) (Staples 1997). The model uses physical properties (aqueous solubility, vapor pressure, soil and sediment distribution coefficient, biota concentration factor) and the assumption that environmental compartments are approximately proportional in size to the natural environment. The model calculates the general distribution of 2-butoxyethanol following the release of 100 moles. The model estimated that at equilibrium about 96% of the 2-butoxyethanol would be found in water, with <0.1%, 2%, <0.1%, <0.1%, and 2% found in air, soil, biota, suspended solids, and sediment, respectively. 

PHYSICAL PROPERTIES water-white to pale yellow liquid weak, peppermint-like odor a mixture of cyclic ketones physical properties, miscibility, and tolerance for non-solvent and solvent action most closely resembles that of cyclohexanone soluble in alcohol and ether not soluble in water MP (-14 C, 7 F) BP (165 C, 329T) DN (0.9250 g/mL liquid at 20 C) LSG (0.93) VD (3.86) REL DN vapor/air mixture (1.004 at 20°C) VP (1 mmHg at 20 C). 

But wait a minute, dear readers. Those of you who have had some high-school chemistry realize that solubilities of alcohol and salt in water are physical properties while solubilities of metals in acids are chemical properties. You would not have received a good grade from me for confusing the two. Clearly, the differences were not yet fully clear to early eighteenth-century scientists. 

When you look at any drug molecule, there are a number of functional groups present that contribute to the properties of that drug molecule. Identify the types of functional groups in each molecule and to which physical properties (water/lipid solubility) each contributes. 

Compound/CAS No. Structure/Functional Group Physical Properties and Solubility in water Uses Toxicity... 

The physical properties of the drag substance and excipients are important in the manufacture, packaging, shipping, and use of drags [1]. These physical properties include solubility, dissolution rate, stability, particle size, water absorption, compactibility, and others. The crystalline form of the solid affects each of these properties. The physical form (i.e. polymorphism) of the drag substance can even affect the bioavailability of the drag and its effectiveness as a medicine [2]. Different solid-state forms of a chemical can be patented, thereby protecting the intellectual property of the pharmaceutical company, which can have a... 

The potential of a compound for use as a sweetener depends upon its physical, processing and sensory properties. Important physical properties are solubility, viscosity of the solutions, and hy-groscopicity. Figure 19.1 shows that the solubility of sugars and their alcohols in water is variable and affected to a great extent by temperature. 

The most common method of classifying vitamins is according to their common physical properties, their solubility in water (in a polar environment) and fat (in a non-polar environment). Vitamins are thus divided into two groups ... 

The present study adds some insight into the interactions between two polymers but, more importantly, illustrates the type of property behavior that can be expected from miscible or immiscible - but compatible - blends which exhibit macroscopically uniform physical properties. The solubility, diffusivity and permeability behavior of numerous series of blends have been evaluated between 1974 and 2012. Whether or not a single phase exists depends on the chemical structure, molar mass distribution, and molecular architecture of the components present. Water, organic solvents and gases have been used as probes in sorption experiments and transport processes incorporating pervaporation, vapor, and gas permeation. 

Physical Properties. All colourless liquids, completely miscible with water, except benzyl alcohol and cyclohexanol, which are slightly soluble. Pure glycol and glycerol have high viscosity, which falls as the hygroscopic liquids absorb water from the air. 

Physical properties. Above members all colourless. Acetone, CH3COCH3, b.p. 56 soluble in water, characteristic odour. Ethyl methyl ketone, b.p. 80°, and diethyl ketone, b.p. 102 , are moderately and sparingly soluble in water respectively. Acetophenone,C6H5COCH3, m.p. 20, sparingly soluble, and benzophenone, m.p.48 ,... 

Physical properties. Acetic anhydride, (CH3C0).20, is a colourless liquid with a sharp pungent odour, decomposed slowly by water, in which it is only slightly soluble. 

Physical properties. Majority are liquids except p toluidine and 1- and 2-naphthylamine. All are colourless when pure, but rapidly darken on exposure to air and light. All are very sparingly soluble in water, but dissolve readily in dilute mineral acids (except the naphthyl-amines, which are only moderately soluble in adds). They form colourless crystalline salts e.g., CjHjNH2,HCl) which are soluble in water these aqueous solutions usually have an add reaction owing to hydrolysis, and give the reactions of both the amine and the acid from which they are derived. Addition of alkali to the acid solution liberates the amine. 

Physical Properties, (i) Triethylamine, b.p. 90 , tri-n-propylamine, b.p. 156 , tri biitylamine, b.p. 212 ", are liquids with a fishy odour, and with decreasing solubility in water. 

Physical Properties All colourless odourless crystalline solids. Acetanilide,CH3CONHCflH5,andbenzanilide,C,H6CONHCeH6 are both sparingly soluble in cold water, but acetanilide has the greater solubility in hot water. 

Physical Properties. Glycine is a colourless crystalline solid soluble in water. Owing to the almost equal opposing effects of the amino and the carboxylic groups. its aqueous solution is almost neutral (actually, slightly acidic to phenolphthalein) and glycine is therefore known as a neutral ampholyte. f It exhibits both acidic and basic properties. 

Physical Properties, Colourless solid when pure, usually pale brown. Sparingly soluble in cold water, soluble in hot water soluble also in cold mineral acids and caustic alkalis. Dissolves readily in cold alcohol, and solution possesses a faint blue fluorescence. 

Physical Properties. Colourless crystalline solid, soluble in boiling water, very sparingly soluble in cold water crystallises 2H2O. The strongly acidic — SO3H group suppresses the normal basic properties of the — NHj group the acid therefore dissolves readily in alkalis, but not in dilute mineral acids. 

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