化学专业英语专题培训课件

1、化学专业 英语 chemist 化学家 equation 方程式 become 适合，与相称 aqueous 水的 radical 基，根，原子团 balance 天平，平衡 acidic 酸的，酸性的 substance 物质 anhydride 酐 sour 酸的，酸味的；变酸 basic anhydride 碱酐 taste 味道，气味，味觉 negative 负的，阴的 lemon 柠檬 acid radical 酸根 orange 柑，桔；橙色 share 共享，分享 citric 柠檬的 transfer 转移 citric acid 柠檬酸 coordinate 配位 citru

2、s 柑桔属 coordinate valence 配键 lactic 乳的 hydronium ion 水合氢离子 lactic acid 乳酸 词汇 litmus 石蕊 soapy 肥皂般的，滑腻的 litmus paper 石蕊试纸 slippery 滑的 dye 染料 neutralization 中和 soak 浸泡，浸渍 evaporation 蒸发 enable 使能够 positive 正的，阳的 indicator 指示剂 positive ion 正离子 methyl 甲基 negative ion 负离子 methyl orange 甲基橙 lattice 格子，点阵 ph

3、enolphthalein 酚酞 crystal lattice 晶格 react (with, on) 反应 electrovalent 电价的 strong acid 强酸 orient 定向，取向 ionize 离子化，电离 pattern 模型，形式 bitter 苦味 The Classes of Compounds 1.Thousands and tens of thousands of compounds are known to the chemist today. It would be impossible to learn properties and behavior

4、of even a fraction of this number if it had to be done on the basis of individual compounds. Fortunately, most chemical compounds can be grouped together in a few classes. Then, if we can properly classify a compound, we are at once aware of the general properties of the compound from knowledge of t

5、he properties of that class or group of compounds. For example, HCl is classed as an acid, and by becoming familiar with the behavior of acids as a distinct class, we are at once aware of the general properties of the compound. A great many of the compounds we are to study may be classified as acids

6、, bases, salts, metallic oxides, or nonmetallic oxides. Of these five classes of compounds, the first three-acids, bases, and salts-are by far the most important. The Classes of Compounds Thousands and tens of thousands of compounds are known to the chemist today. 化合物分类 现今，化学家知道了成千上万的化合物。 ? thousand

7、s and tens of thousands成千上万 ? be known to被所知 chem(o) 化学（的） chemistry 化学 chemical 化学的，化学药品 chemosynthesis 化学合成 It would be impossible to learn properties and behavior of even a fraction of this number if it had to be done on the basis of individual compounds. 如果根据个别化合物来了解这么多化合 物的性质，即使其中的一小部分也是不可 能的。

8、? a fraction of 一小部分 ? on the basis of 根据, 在基础上 Fortunately, most chemical compounds can be grouped together in a few classes. 幸运的是，大多数化合物能够组合在一起分成几类。幸运的是，大多数化合物能够组合在一起分成几类。 Then, if we can properly classify a compound, we are at once aware of the general properties of the compound from knowledge of

9、 the properties of that class or group of compounds. 那么，如果我们能够恰当地将一个化合物归类，我们立 刻就能从这类化合物的性质来了解这个化合物的一般性 质。 ? be aware of 知道，意识到 For example, HCl is classed as an acid, and by becoming familiar with the behavior of acids as a distinct class, we are at once aware of the general properties of the compou

10、nd. ? become (be) familiar with熟悉，通晓 例如，盐酸归类为酸，由于已熟悉作为不同类别 的酸的性质，我们就会立即知道这一化合物的一 般性质。 A great many of the compounds we are to study may be classified as acids, bases, salts, metallic oxides, or nonmetallic oxides. Of these five classes of compounds, the first three-acids, bases, and salts-are by far

11、 the most important. 我们将要研究的众多化合物可以分类为酸、碱、盐、 金属氧化物或非金属氧化物。这五类化合物中的前三类 酸、碱和盐是最重要的。 ? a great （good）many of 很多，大量 2. When an acid, base, or salt is dissolved in water the resulting solution is a conductor of the electric current and is termed an electrolyte. If no conduction of current occurs, the com

12、pound is known as a nonelectrolyte. 2. When an acid, base, or salt is dissolved in water the resulting solution is a conductor of the electric current and is termed an electrolyte. If no conduction of current occurs, the compound is known as a nonelectrolyte. 酸、碱或盐溶于水中得到的溶液是电流的导体， 它们被定义为电解质。如果没有电流的传

13、导发生， 这种化合物被称为非电解质。 ? conductor 导体 ? electric current 电流 ? term 被称作 ? electrolyte/nonelectrolyte 电解质，非电解质 3. Classification of Common Compounds By looking at the chemical formulas we may classify many common compounds in the following way. 1. Acids, in the conventional sense, may be recognized by not

14、ing that the H is written first in the formula and that the rest of the compound is generally nonmetallic. Ex., HCl, H 2SO4, HClO. 2. Conventional bases have OH radicals written last in the formula. The first part of the formula is usually a metal. Ex., NaOH, Ca(OH) 2, Fe(OH)3. 3. A salt consists of

15、 a metal, written first, combined with a non-metal or radical written last in a formula. Ex., NaCl, Fe 2(SO4)3, Ca(ClO)2. 4. Oxides are compounds containing oxygen and only one other element. Classification of Common Compounds By looking at the chemical formulas we may classify many common compounds

16、 in the following way. 普通化合物分类 我们可以根据化学式按着下面的方法分类许多普 通化合物。 ? Class n, 类别 ? Classify Vt.分类 ? Classification n. 分类 1. Acids, in the conventional sense, may be recognized by noting that the H is written first in the formula and that the rest of the compound is generally nonmetallic. Ex., HCl, H2SO4, HC

17、lO. ? in the conventional sense按传统的观念（常识） 1.按传统的观念，可以通过在分子式中将按传统的观念，可以通过在分子式中将H写在第一位写在第一位 并且化合物中的其余部分通常是非金属来辨认出酸，例并且化合物中的其余部分通常是非金属来辨认出酸，例 如，如， HCl, H 2SO4, HClO。 。 2. Conventional bases have OH radicals written last in the formula. The first part of the formula is usually a metal. Ex., NaOH, Ca(OH)

18、2, Fe(OH)3. 2. 传统碱的分子式中将 OH基写在最后 面。分子式的第一部分通常是一种金属。 例如， NaOH, Ca(OH)2, Fe(OH)3。 3. A salt consists of a metal, written first, combined with a non-metal or radical written last in a formula. Ex., NaCl, Fe2(SO4)3, Ca(ClO)2. 3. 盐的分子式由写在第一位的金属和写在最 后一位的非金属或原子团组成。例如，NaCl, Fe2(SO4)3, Ca(ClO)2。 4. Oxides ar

19、e compounds containing oxygen and only one other element. 4. 氧化物是由氧和唯一一种其它元素组成的化合氧化物是由氧和唯一一种其它元素组成的化合 物。 4. If the element other than oxygen is a nonmetal, the oxide classed as a nonmetal oxide or an acidic anhydride. The latter name comes about because water added to nonmetal oxides under certain c

20、onditions produces acids. Likewise, if water is removed from an acid containing oxygen, the acid anhydride (without water) results. If the element other than oxygen is a nonmetal, the oxide classed as a nonmetal oxide or an acidic anhydride. ?other than 除了，不同于除了，不同于 ?anhydr ide 酐 anhydr(o) 脱水，无水，酐 a

21、nhydr ation脱水，干化 anhydr ous 无水的 anhydro glucose脱水葡萄糖 如果除氧以外的元素是非金属，这种氧化物被称为非金 属氧化物或酸酐。 The latter name comes about because water added to nonmetal oxides under certain conditions produces acids. 酸酐的名称来源于在一定条件下将水加到非金属 氧化物中能够生成酸。 ? come about 产生，发生，出现 Likewise, if water is removed from an acid contain

22、ing oxygen, the acid anhydride (without water) results. 同样，如果将水从含氧酸中除去，就会生成酸酐（没同样，如果将水从含氧酸中除去，就会生成酸酐（没 水）。水）。 ? acid containing oxygen含氧酸 5. The other class of oxides, metallic oxides or basic anhydrides, consist of oxygen combined with a metal. When water is added under proper conditions to basic a

23、nhydrides, bases result and vice versa. The other class of oxides, metallic oxides or basic anhydrides, consist of oxygen combined with a metal. ? basic anhydride 碱酐 另一类氧化物，金属氧化物或碱酐，由氧另一类氧化物，金属氧化物或碱酐，由氧 和一种金属组成。 When water is added under proper conditions to basic anhydrides, bases result and vice v

24、ersa. 在合适的条件下将水加到碱酐中就会产生碱，在合适的条件下将水加到碱酐中就会产生碱， 反之亦然。反之亦然。 ? vice versa 反之亦然 6 Acids All acids in the conventional sense contain hydrogen, which may be replaced by metals. The negative portion of the acid molecule is composed of a nonmetal or a radical (negative valence group). These negative valence

25、 groups (except oxide and hydroxide) are often referred to acid radicals. All acids are covalent compounds in which the atoms are held together by a sharing of electrons. When an acid is dissolved in water, ions are formed as a result of the transfer of a hydrogen ion (proton) from the acid molecule

26、 to the water molecule-for example, ClH . . . . HOH . . . . HHO H . . . . + + +Cl . . . . _ Acids All acids in the conventional sense contain hydrogen, which may be replaced by metals. 酸 按传统意义，所有酸都含有氢，并且氢能 够被金属取代。 The negative portion of the acid molecule is composed of a nonmetal or a radical (nega

27、tive valence group). 酸分子中负电部分由一种非金属或原子团 (负价基团)组成。 ? Radical 根、原子团 These negative valence groups (except oxide and hydroxide) are often referred to acid radicals. 这些负价基团（除氧化物和氢氧化物外 ) 通常被定义为酸根。 ? valence 化合价 ? acid radicals 酸根 All acids are covalent compounds in which the atoms are held together by a

28、sharing of electrons. 所有酸都是共价化合物，在化合物中原子所有酸都是共价化合物，在化合物中原子 通过电子共享结合在一起。 ? covalent compounds共价化合物 When an acid is dissolved in water, ions are formed as a result of the transfer of a hydrogen ion (proton) from the acid molecule to the water molecule-for example, ClH . . . . HOH . . . . HHO H . . . .

29、 + + +Cl . . . . _ ? 当酸溶于水中，酸分子中的氢离子（质子） 从酸中迁移到水分子中形成离子，例如： ClH . . . . HOH . . . . HHO H . . . . + + +Cl . . . . _ 7. This is a case of coordinate valence, in which an unused pair of electrons from the water molecule combines with a hydrogen ion to from a hydronium ion. The hydronium ion is a hydra

30、ted hydrogen ion or proton ( H+ H2O) and, while the ionization of acids in aqueous solution depends on its formation, we shall ordinarily use the simple H+ in writing equations. Such equations are thereby simplified and easier to balance. This is a case of coordinate valence, in which an unused pair

31、 of electrons from the water molecule combines with a hydrogen ion to form a hydronium ion. 这是配位键的一个例子，在配位键中水分子中这是配位键的一个例子，在配位键中水分子中 未被使用的电子对同氢离子结合形成水合氢离 子。 ? coordinate valence 配位键 ? combine with 与结合 ? hydronium ion 水合氢离子 The hydronium ion is a hydrated hydrogen ion or proton ( H + H2O) and, while

32、the ionization of acids in aqueous solution depends on its formation, we shall ordinarily use the simple H+ in writing equations. Such equations are thereby simplified and easier to balance. 水合氢离子是一种含水的氢离子或质子 ( H+ H2O) ， 并且酸通过形成水合氢离子在水溶液中电离，在书写 方程式时，我们通常写成简单的 H+ 。因此，方程式被 简化了，并且更容易配平。 ?hydronium ion

33、= hydrated hydrogen ion 水合氢离子 ?Hydrate 与水化合 ；Hydrated 与水化合的，含水的 ?Ionization 离子化、电离 ?Equations 方程式 ?Thereby 因此 8. The chief characteristic of an acid is its ability to furnish hydrogen ions (protons); therefore, an acid is usually defined as a substance which may furnish protons. The chief characteri

34、stic of an acid is its ability to furnish hydrogen ions (protons); therefore, an acid is usually defined as a substance which may furnish protons. ? furnish 提供，供给 ? be defined as 定义为 酸的主要性质是能够提供氢离子（质子），因 此，酸通常被定义为能够提供质子的物质。 9. Properties of Acids. In general, aqueous solutions of acids are character

35、ized by the following properties: 1. They have a sour taste. Lemons, oranges, and other citrus fruits owe their sour taste to the presence of citric acid; the taste of sour milk is due to the presence of lactic acid. 2. They turn blue litmus paper red. Litmus is a dye which has a red color in acid s

36、olution and a blue color in basic solution; paper which has been soaked in litmus is referred to as litmus paper. Substances of this type, which enable us to determine whether a given solution is acid or basic, are called indicators. Methyl orange and phenolphthalein are other indicators frequently

37、used by chemists. 3. They react with certain metals to produce hydrogen. Reactions of this type were studied in connection with the preparation of hydrogen. 4. They react with bases to produce salts and water. Properties of Acids. In general, aqueous solutions of acids are characterized by the follo

38、wing properties: 酸的性质。通常，酸的水溶液具有下面的性质： ? aqueous 水的 ? properties 性质 1. They have a sour taste. Lemons, oranges, and other citrus fruits owe their sour taste to the presence of citric acid; the taste of sour milk is due to the presence of lactic acid. 1. 它们有酸味。柠檬、橙子和其它柑它们有酸味。柠檬、橙子和其它柑 桔属水果由于含有柠檬酸而有酸味

39、；酸牛 奶的酸味是由于乳酸的存在。 2. They turn blue litmus paper red. Litmus is a dye which has a red color in acid solution and a blue color in basic solution; paper which has been soaked in litmus is referred to as litmus paper. 2. 它们使蓝色石蕊试纸变红。石蕊是一种在酸溶 液中显红色，在碱溶液中显蓝色的染料；已经被 浸渍在石蕊中的纸称为石蕊试纸。 Substances of this type

40、, which enable us to determine whether a given solution is acid or basic, are called indicators. Methyl orange and phenolphthalein are other indicators frequently used by chemists. ? enable to 使能够 ? Indicators 指示剂 ? Methyl orange 甲基橙 ? phenolphthalein 酚肽 能够用来确定某一特定溶液是酸性或碱性的这类物质称能够用来确定某一特定溶液是酸性或碱性的这类

41、物质称 为指示剂。甲基橙和酚酞是经常被化学家使用的另一些为指示剂。甲基橙和酚酞是经常被化学家使用的另一些 指示剂。指示剂。 3. They react with certain metals to produce hydrogen. Reactions of this type were studied in connection with the preparation of hydrogen. 4. They react with bases to produce salts and water. 3. 它们和某些金属反应产生氢气。这类反应在氢气 制备方面被研究。 4. 它们和碱反应生成盐

42、和水。 ?in connection with 与有关，在.方面 10. Common strong acids are H2SO4, HNO3, HCl, HBr, and HI. Most other acids are generally only partially ionized and consequently only moderately strong or weak. Common strong acids are H2SO4, HNO3, HCl, HBr, and HI. Most other acids are generally only partially ioni

43、zed and consequently only moderately strong or weak. 普通的强酸有 H2SO4、HNO 3、HCl、HBr和 HI。大多数 其它酸通常只部分电离，因此它们只是中强酸或弱酸。 11. Bases All metallic hydroxides are classed as conventional bases. Of the common bases only NaOH, KOH, Ca(OH)2 and Ba(OH)2 are appreciably soluble in water. If these compounds are disso

44、lved in water, the OH- is common to all of their solutions. Bases All metallic hydroxides are classed as conventional bases. Of the common bases only NaOH, KOH, Ca(OH)2 and Ba(OH)2 are appreciably soluble in water. If these compounds are dissolved in water, the OH- is common to all of their solution

45、s. ? appreciably 略微，有一点 所有的金属氢氧化物被归类为传统的碱。在普通的碱 中，只有NaOH, KOH, Ca(OH) 2 和 Ba(OH)2 略微可溶 于水。如果这些化合物溶于水中，均产生 OH-。 An aqueous solution of NH 3 is also classed as a base, since OH- ions are present in the solution. NH3的水溶液也归类为碱，这是的水溶液也归类为碱，这是 因为在水溶液中存在OH- 。 12. In each of these compounds we find a combin

46、ation of a metal (or NH4) with the hydroxide group. Just as the characteristic part of an acid is hydrogen ion, so the characteristic part of a base in water solution is the hydroxide ion, OH-. Later the concept of a base will be extended to include substances which do not furnish hydroxide ions in

47、solution. In each of these compounds we find a combination of a metal (or NH4) with the hydroxide group. 我们发现这些化合物中的每一个都由一 种金属（或NH4 ）和氢氧根组成。 Just as the characteristic part of an acid is hydrogen ion, so the characteristic part of a base in water solution is the hydroxide ion, OH -. 正如酸的特征部分是氢离子，碱在水

48、溶液中的 特征部分是氢氧根离子，OH-。 ? Just as, so正如那样 Later the concept of a base will be extended to include substances which furnish hydroxide ions in solution. 后来，碱的概念被扩展到包括在溶液中没有提 供氢氧根离子的物质。 13.Properties of Bases . In general, water solutions of metallic hydroxides (bases) exhibit the following properties. 1.

49、 Bitter taste. 2. Soapy or slippery feeling. 3. Turn red litmus paper blue. 4. React with acids to form salts and water. 5. Most metallic hydroxides are insoluble in water. Of the common ones, only NaOH, KOH, Ca(OH) 2, Ba(OH)2, and NH3 are soluble. The common strong bases are NaOH, KOH, Ca(OH) 2, an

50、d Ba(OH)2. Properties of Bases. In general, water solutions of metallic hydroxides (bases) exhibit the following properties. 碱的性质。通常，金属氢氧化物 （碱）具有下面的性质。 1. Bitter taste. 2. Soapy or slippery feeling. 3. Turn red litmus paper blue. 4. React with acids to form salts and water. 1. 苦味。 2. 滑腻感。滑腻感。 3. 使红色石蕊试纸变蓝。 4. 同酸反应生成盐和水。 5. Most metallic hydroxides are insoluble in water. Of the common ones, only NaOH, KOH, Ca(OH)2, Ba(OH)2, and NH3 are soluble. The common strong bases are NaOH, KOH, Ca(OH)2, and Ba(OH)2. 5. 大多数金属氢氧化物难溶于水。普通的氢氧化物 中，只有NaOH, KOH, Ca(OH) 2, Ba(OH)2和NH3是可 溶的。 普通强碱有NaOH, KOH