专业外语.无机化合物的分类.ppt

Most other acids are generally only partially ionized and consequently only moderately strong or weak. 其它的大部分酸一般仅部分解离，因此仅仅是中等强度或者很弱。 * All metallic hydroxides are classed as conventional bases. 所有的金属氢氧化物都归类为传统意义上的碱。 Of the common bases only NaOH, KOH, Ca(OH)2 and Ba(OH)2 are appreciably（略微，有一点） soluble in water. 在常见的碱中，只有NaOH、KOH、Ca(OH)2 和Ba(OH)2在水中略微溶解。 Bases 碱 * If these compounds are dissolved in water, the OH- is common to all of their solutions. 如果这些化合物溶解在水中，OH-的存在是所有这些溶液的共同特征。 An aqueous solution of NH3 is also classed as a base, since OH- ions are present in solution. NH3的水溶液也划分为碱类，因为它的溶液中也存在OH-。 In each of these compounds we find a combination of a metal (or NH4+) with the hydroxide group. 在这些化合物中，我们都会发现金属或（NH4+）与氢氧根的结合。 * Just as the characteristic part of an acid is hydroxide ion（应该是hydronium ion）, so the characteristic part of a base in water solution is the hydroxide ion, OH-. 正象酸的水溶液的特征部分是水合氢离子，碱的水溶液的特征部分是OH-。 Later the concept of a base will be extended to include substances which do not furnish hydroxide ions in solution. 后来碱的概念延伸到包括溶液中不提供（不存在）OH-的物质。 * Properties of Bases. 碱的性质： In general，water solution of the metallic hydroxides ( bases ) exhibit the following properties: 一般，金属氢氧化物（碱）的水溶液表现出以下性质： 1. Bitter taste. 苦味 2. Soapy or slippery feeling. 滑腻感 3. Turn red litmus paper blue. 使蓝色石蕊试纸变红。 * 4. React With acids to form salts and water. 与酸反应产生盐和水。 5. Most metallic hydroxides are insoluble in water. 大部分金属氢氧化物都难溶于水。 Of the common ones, only NaOH, KOH, Ca(OH)2, Ba(OH)2，and NH3 are soluble. 在常见的金属氢氧化物中，只有NaOH、KOH、Ca(OH)2、Ba(OH)2、和 NH3易溶解于水。 The common strong bases are NaOH, KOH, Ca(OH)2, and Ba(OH)2. NaOH、KOH、Ca(OH)2和Ba(OH)2是常见的强碱。 * Salts 盐 An acid reacts with a base to produce a salt and water. 酸与碱反应产生盐和水。 Hydrogen from the acid combines with hydroxide from the base to form water molecules. 酸中的氢与碱中的氢氧根结合形成水分子。 The reaction of an acid with a base is called neutralization. 酸与碱的反应叫做中和反应。 * If all the water is removed by evaporation from th