Санкт-петербургского государственного университета высшее профессиональное образование т. А. Степанова, И. Ю. Ступина
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1stepanova t a english for chemists
| THE ADVERBIAL MODIFIER
Lesson 28 ГРАММАТИКА: Обстоятельство. Существительное, наречие, герундий и герундиальный оборот в функции обстоятельства. Scction I Ex. 1. Practise your reading. As long ago as 1833, it was concludcd that clcctrolysis took placc through the transport of cicctricity by mobile charged particlcs. Ex. 2. State what parts of speech the following words belong to: clcctron, clcctronic, clcctricity, clcctric, clcctrical, clcctrify, clcctro- chcmistry, clcctrolytc, clcctrolysis, electrolytic, clcctrolyzc, clcctrodc, clcctrostatic Ex. 3. Define the meanings of the word number in the following sentences: 1. There arc a number of difficulties in the analysis of such systems. 2. My telephone number is 2530744. 3. Since the atomic number o f hydrogen is 1, a single clcctron makes the atom clcctrically neutral. 4. An ion is regarded to have an clcctrovalcncc equal in number and sign to its chaige. 5. The number of different kinds of molcculcs is enormous. 6. There arc a number o f steps which arc common to all metallurgical processes involved in extracting a metal from its ores. 7. An idea able to explain or correlate a number o f facts is called a hypothesis. 8. A great number of methods arc now in use preparing silicon. Ex. 4. Analyse the following sentence: A good deal of succcss in the study of molcculcs in the gas phase prompted chemists to attempt to build up theories of solutions in an analogous way. 184 Text 28 A Interactions in Electrolyte Solutions In a solution of an cicctrolytc, it is often ncccssary to have a detailed knowledge of the spccics present. New ions or uncharged molcculcs resulting from interactions in the solution may behave quite differently from the constituent ions of the cicctrolytc. Some properties o f the solutions will be profoundly affcctcd, and the chcmist, in order to understand these phenomena, will require to know the nature of the spccics present. There arc a number o f formidable difficulties in the analysis of such systems and, during the past forty years or so, a great deal of work has been done on the problem. The equilibrium properties of cicctrolytc solutions and the way in which ion-pair and complex formation can be dctcctcd and quantitatively studied arc of primary importance. Although the application of new physical and chcmical methods has produced significant contributions in this field, the information obtained from measurements of a system at equilibrium is to some extent limited, and in studying the phenomenon it is desirable to know the relevant kinetic parameters. Without this understanding, it is sometimes impossible to sketch the actual reaction mechanism by which the system approaches equilibrium. In general, wc may regard the elucidation of the structure of an cicctrolytc solution as a difficult problem which requires as many independent lines of attack as possible. A good deal of succcss in the study o f molcculcs in the gas phase prompted chcmists to attempt to build up theories o f solutions in an analogous way. The classical theories regarded the solvent as merely providing spacc in which the solute particles moved and interactions between the ions and the solvent molcculcs were neglected. This 0 assumption can be questioned on the basis of even the most elementary electrostatic considerations. As long ago as 1833, both Faraday and Danicll concluded that electrolysis took placc through the transport of clcctricity by mobile charged жүктеу/скачать 5,96 Mb. Достарыңызбен бөлісу:
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