Практикалық сабақтарының тақырыптары мен мазмұны Practical assignment №1
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the solution of interest - исследуемый раствор will plate out - отлагается to reduce some but not all - для частичного удаления ION EXCHANGE Another procedure utilizing the elution technique is the ion exchange separation. This time the solid (which is called the substrate) is a salt or compound withsalt-forming capacity, something like a sulfonic acid group. When a solution containing metal ions is passed through such an acid substrate, the ions can replace the protons, forming salts. Further elution repeats many times the cycle of ion exchange, replacement of a proton by a salt ion, followed by replacement of the metal ion by proton. As in chromatography, the repetitious procedure magnifies small differences in saltforming capacity and permits separations which are extremely difficult by any other method. Ion exchange substrates fall into two groups: cation exchangers and anion exchangers. Acidic functional groups areeffective as cation exchangers. These groups include sulfonic acids,— SO3H; carboxylic acid,— COOH; phenols or alcohols,— OH; and mercaptans,— SH. These interact only with cations and by an exchange reaction of the following sort: — SO3H + M+ = — SO2M + H+. Most anion exchangers are amines, depending upon one of the functional groups — NH2,— NHR, and NR2. These groups form ammonium type salts, and the anion can be displaced: — NH2 • HC1 + X = — NH2 • HX + Cl. 1. saltforming capacity - способность солеобразования 2. something like - нечто вроде 3. by any other method - любым другим методом 4. fall into two groups - разделяются на две разные группы WORDPERFECT Vocabulary: Drill Exercises Terminology Dictionary. Study the chemical terms in the texts above and make a list of them in your vocabulary copybook ACADEMIC WRITING Written Description on the theme Essay Writing Pattern in English Letter Writing in English: Covering Letter. жүктеу/скачать 64,23 Kb. Достарыңызбен бөлісу:
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