翻訳と辞書 |
Solvent
A solvent (from the Latin ''solvō'', "I loosen, untie, I solve") is a substance that dissolves a solute (a chemically different liquid, solid or gas), resulting in a solution. A solvent is usually a liquid but can also be a solid or a gas. The quantity of solute that can dissolve in a specific volume of solvent varies with temperature. Common uses for organic solvents are in dry cleaning (e.g., tetrachloroethylene), as paint thinners (e.g., toluene, turpentine), as nail polish removers and glue solvents (acetone, methyl acetate, ethyl acetate), in spot removers (e.g., hexane, petrol ether), in detergents (citrus terpenes) and in perfumes (ethanol). Water is a solvent for polar molecules and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within a cell. Solvents find various applications in chemical, pharmaceutical, oil and gas industries, including in chemical syntheses and purification processes. The global solvent market is expected to earn revenues of about US$33 billion in 2019. The dynamic economic development in emerging markets like China, India or Brazil will especially continue to boost demand for solvents. Specialists expect the worldwide solvent consumption to increase at an average annual rate of 2.5% over the subsequent years. Accordingly, the growth rate seen during the past eight years will be surpassed.〔(Market Study on Solvents ). Ceresana Research〕 ==Solutions and solvation== When one substance is dissolved into another, a solution is formed.〔Tinoco, Ignacio; Sauer, Kenneth and Wang, James C. (2002) ''Physical Chemistry'' Prentice Hall p. 134 ISBN 0-13-026607-8〕 This is opposed to the situation when the compounds are insoluble like sand in water. In a solution, all of the ingredients are uniformly distributed at a molecular level and no residue remains. A solvent-solute mixture consists of a single phase with all solute molecules occurring as ''solvates'' (solvent-solute complexes), as opposed to separate continuous phases as in suspensions, emulsions and other types of non-solution mixtures. The ability of one compound to be dissolved in another is known as solubility; if this occurs in all proportions, it is called miscibility. In addition to mixing, the substances in a solution interact with each other at the molecular level. When something is dissolved, molecules of the solvent arrange around molecules of the solute. Heat transfer is involved and entropy is increased making the solution more thermodynamically stable than the solute and solvent separately. This arrangement is mediated by the respective chemical properties of the solvent and solute, such as hydrogen bonding, dipole moment and polarizability.〔Lowery and Richardson, pp. 181–183〕 Solvation does not cause a chemical reaction or chemical configuration changes in the solute. However, solvation resembles a coordination complex formation reaction, often with considerable energetics (heat of solvation and entropy of solvation) and is thus far from a neutral process.
抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Solvent」の詳細全文を読む
スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|