Dissolving power

Mineral acids include hydrochloric acid and blends of hydrochloric and hydrofluoric acid (usually 12% HCl/3% HF). Hydrochloric acid is used to acidize carbonate formations. Its advantages are relatively low cost, high carbonate mineral dissolving power, and the formation of soluble reaction products (which minimizes formation damage). The primary disadvantage of hydrochloric acid is its corrosive nature. 

Introduction In this experiment, the miscibility of water with some common organic solvents and the dissolving power of water, hydrochloric acid, sulfuric acid, and nitric acid will be studied. First, small amounts of water will be mixed with roughly equal amounts of the organic solvents, and the miscibilities will be observed. Then small volumes of water and the acids will be allowed to contact granules of some selected metals and other compounds, and their dissolving power will be noted. The objectives are to confirm some of the statements made in Tables 2.1, 2.2, and 2.3 and to discover the behavior of some solvents and acids not listed. 

It is also important for recrystallisation from hot saturated solution that the temperature-solubility curve should rise as steeply as possible, i.e. that the dissolving power of the solvent should increase greatly with increasing temperature. In that case only can the amount of substance taken be recovered from the solution in the highest possible yield. 

The significant, often decisive, influence of the solvent in chemical reactions similarly is valid for electrochemical reactions too, for example, due to protic or aprotic and electrophilic or nucleophilic properties. If an excess of reactants can be used as solvent, a particularly uncomplicated operation will be possible. An additional solvent should be inert. The requirements for the solvent in dissolving power for reactants and products and the criteria regarding an easy separation of the products from the reaction mixture, for example, the boiling point, are comparable for chemical and electrochemical conversions. Generally, there is an interest to use, as far as possible, inexpensive, nontoxic, and easy to handle solvents. 

Petroleum solvents (also called naphtha) are valuable because of their good dissolving power. The wide range of naphtha available and the varying degree of volatility possible offer products suitable for many uses. 

The variety of applications emphasizes the versatility of naphtha. For example, naphtha is used in paint, printing ink, and polish manufacturing and in the rubber and adhesive industries, as well as in the preparation of edible oils, perfumes, glues, and fats. Further uses are found in the dry-cleaning, leather, and fur industries and in the pesticide field. The characteristics that determine the suitability of naphtha for a particular use are volatility, solvent properties (dissolving power), purity, and odor (generally the lack thereof). 

Dissolving power In general dissolves more substances and in greater quantities than any other liquid Obvious implications in both physical and biological phenomena... 

Where no single solvent is found suitable, a mixture of two mixable solvents, one of which the product is soluble and the other insoluble, may be used. The substance is dissolved in a small quantity of the solvent that has the strongest dissolving power, then the solvent that does not dissolve the product, is added until complete crystallization occurs. This process can be carried... 

David Macbride, a prominent surgeon of Dublin, was the next to contribute to the chemistry of gases. He published a work entitled Experimental Essays in 1764. Macbride was especially interested in the fermentation processes in the animal body. Knowing that fixed air was an important product of these fermentations, he was led to investigate fixed air. His book consists of five essays, two of which, On the nature and properties of fixed air, and On the dissolvent power of quicklime, contain his contribution to the knowledge of fixed air. 

Take a pound of Cyprus vitriol, a pound and a half of saltpetre, and a quarter of a pound of alum. Submit the whole to distillation in order to withdraw a liquor which has a high solvent action. The dissolving power of the acid is greatly augmented if it be mixed with some sal ammoniao, for it will then dissolve gold, silver, and sulphur. 

If solvents are used which do not possess a high dissolving power for both kinds of blocks (high second virial coefficients of osmotic pressure), phase separation occurs at considerably lower concentrations, and the solvent content of the aggregates is lower than that of the matrix. 

A supercritical fluid is in a state where matter is compressible and behaves as a gas (i.e., it fills and takes the shape of its container), which is not the case when it is in a liquid state (an incompressible fluid that occupies the bottom of its container). Moreover, a supercritical fluid has the typical density of a liquid (between 0.1 and 1.0 g/mL), which results in its characteristic dissolving power. Thus, a supercritical fluid can be defined as a heavy gas with a controllable dissolving power or as a form of matter in which the liquid and gaseous state are indistinguishable [16-18]. 

Although ethers are relatively inert toward reaction, they usually show good solvent properties for many nonpolar organic compounds. This strong dissolving power coupled with low reactivity makes ethers good solvents in which to run reactions. 

Saul is represented as being wroth with David, because of the people singing, "Saul hath slain his thousands, but David hath slain his ten thousands," which accords with the actual work. The original dissolving power of Sol (Saul) is nothing compared to its subsequent potency and virtue, or when the active Salt begins its operation, which Salt in the parable is David. 

Parallelism found in the present work between increasing donor activity and dissolving power of methyl derivatives of benzene confirms the assumption of existing charge-transfer interaction between Cf,o molecules and molecules of methyl derivatives of benzene. 

The comparative study of literature data has revealed the parallels between donor force of alkyl derivatives of benzene and their dissolving power relative to C6o fullerene. 

The use of supercritical fluids in extraction processes has become well established. Until now, the extraction of liquids, as for example vitamins or vegetable edible oils, has been carried out in countercurrent columns. Dense gases offer several advantages over conventional solvents such as selective dissolving power, reduced thermal stress of the products or its physiological harmlessness. A supercritical fluid also has a density close to those for liquids, the viscosity is nearly 100 times lower and the diffusivity is up to 100 times higher than those of ordinary liquids as can be seen in table 1. 

The selection of solvent depends, in the first place, on its dissolving power. Subject to this primary requirement, the solvent should have boiling point between 60 and 85 C. For most purposes, petroleum ether boiling around 80 C is used. Other suitable solvents are benzene, cyclohexane, chloroform, carbon tetrachloride, carbon disulphide, ethyl alcohol, acetic acid and ethyl acetate. 

Some of the historical perspective is extracted (no pun intended) from a previous paper of the author ( 1 ) and is expanded with a chronological development of solubility phenomena based upon an additional compilation of recent work on naphthalene-supercritical solvent systems. The new data on flavor extraction and fractionation point out the most unique feature of supercritical fluid solvents, viz., their often-demonstrated selective dissolving power properties, a selectivity that is achieved because the dissolving power of supercritical fluids is pressure-dependent and can, therefore, be adjusted. 

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