應(yīng)用化學(xué)專業(yè)英語第二版萬有志主編版(課后答案和課文翻譯)

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Unit 1 The Roots of Chemistry I. Comprehension. 1.C 2. B 3. D 4. C 5. B II. Make a sentence out of each item by rearranging the words in brackets. 1. The purification of an organic compound is usually a matter of considerable difficulty, and it is necessary to employ various methods for this purpose. 2. Science is an ever-increasing body of accumulated and systematized knowledge and is also an activity by which knowledge is generated. 3. Life, after all, is only chemistry, in fact, a small example of chemistry observed on a single mundane planet. 4. People are made of molecules; some of the molecules in people are rather simple whereas others are highly complex. 5. Chemistry is ever present in our lives from birth to death because without chemistry there is neither life nor death. 6. Mathematics appears to be almost as humankind and also permeates all aspects of human life, although many of us are not fully aware of this. III. Translation. 1. (a) chemical process (b) natural science (c) the technique of distillation 2. It is the atoms that make up iron, water, oxygen and the like/and so on/and so forth/and otherwise. 3. Chemistry has a very long history, in fact, human activity in chemistry goes back to prerecorded times/predating recorded times. 4. According to/From the evaporation of water, people know/realized that liquids can turn/be/change into gases under certain conditions/circumstance/environment. 5. You must know the properties of the material before you use it. IV. Translation 化學(xué)是三種基礎(chǔ)自然科學(xué)之一，另外兩種是物理和生物。自從宇宙大爆炸以來，化學(xué)過程持續(xù)進(jìn)行，甚至地球上生命的出現(xiàn)可能也是化學(xué)過程的結(jié)果。人們也許認(rèn)為生命是三步進(jìn)化的最終結(jié)果,第一步非?？?其余兩步相當(dāng)慢。這三步是：（I）物理進(jìn)化（化學(xué)元素的產(chǎn)生），（II）化學(xué)進(jìn)化（分子和生物分子的形成）；和（III）生物進(jìn)化（有機(jī)物的形成和發(fā)展）。 V. Solution: （1）The relative mass of 1H and 12C atoms can be calculated from their absolute masses in grams. If the mass of a 12C atom is exactly 12 amu,then the mass of a 1H atom to five significant figures must be 1.0078 amu. 12 amu x 0.083986 = 1.0078 amu （2） First we calculate k and then use the first-order rate equation. The bone was tossed away (more precisely, the animal whose bone was died) about 6100 years ago, or about 4100 B.C. We can thus be sure that a village was in existence at that place at that time. Unit 7 The Nomenclature of Inorganic Substances I. Comprehension 1.A 2.B 3.C 4.C 5.B II. Give the systematic name for the following ammonium ion ; copper(II) ion ; strontium ion; Ccopper(I) ion; iron(II) ion; zinc ion; hydrogen ion; lead((II) ion; aluminum; silver ion; magnesium ion; chromium(III) ion; Barium ; Manganese(II) ion; iron(III) ion; calcium ion; mercury(II) ion; chromium(II) ion; tin(II) ion. carbon monoxide; ditrogen trioxide; carbon dioxide; diphosphorus pentoxide; sulfur trioxide; dichlorine heptoxide arsenate ion; sulfite ion; hydride ion; arsenite ion; bromide ion; hydroxide ion; phosphate ion; chlorate ion; hypochlorite ion; phosphate ion; chloride ion; iodate ion; carbonate ion; chlorite ion; nitrate ion; chromate ion; cyanide ion; iodide ion; dichromate ion; fluoride ion; nitrate ion; oxide ion; hydrogen carbonate ion; nitrite ion; sulfide ion; hydrogen sulfate ion; perchlorate ion; sulfate ion; hydrogen sulfite ion; permanganate ion. III. Complete the table. Formula Old name Systematic name FeO iron (II) oxide Fe2O3 iron (III) oxide Sn(OH)2 tin(II) hydroxide Sn(OH)4 tin(IV) hydroxide Hg2SO4 mercury (I) sulfate HgSO4 mercury (II) sulfate NaCLO sodium hypochlorite K2Cr2O7 potassium dichromate Cu3(AsO4)2 copper(II) arsenate Cr(C2H3O2)3 chromium(IV) acetate IV. Acid names may be obtained directly from its acid ion by changing the name of the acid ion (negative ion). Use the rule to give the name of the following acid. Formula of acid Old name Name of acid H2CO3 carbonic acid HClO2 chlorous acid HClO4 perchloric acid HCN hydrocyanic acid HBr hydrobromic acid H4SiO4 silicic acid H3AsO4 arsenic acid V. Complete the sentences with the proper form of the word given at the end of the sentence. 1.is altered; 2.To illustrate 3.indicates 4.should expect 5.would cancel 6. are pulled 7.depend on 8.are; referred 9.formed 10.have discussed VI. Translation 1. Matter can neither be created nor be destroyed/eliminated. 2. It is necessary that a scientist must know how to use fingures to get an accutate answer to question. 3. Any substance is made of atoms whether it is solid, liquid or gas. 4. The experiment was successful. It’s results was the same as what we had expected. 5. It will not be long before we finish the experiment. VII. Write equations for the following acid-base reactions. Use the information in inorganic textbook to predict whether the equilibrium will favor the reactants or the products. (Partially Solved) Solutin to (a): Cyanide is the conjugate base of HCN. It can accept a proton from formic acid: Reading from inorganic textbook, formic acid (pKa=3.76) is a stronger acid than HCN (pKa=9.22), and cyanide is a stronger base than formate. The products (weaker acid and base) are favored. ………….. VIII. Write equations for the net reactions which occur when the following materials are added to a sodium-ammonia solution. Answer: (1) 2CH3GeH3 + 2eam- → H2 + 2CH3GeH2- (2) I2 + 2eam- → 2I- (3) (C2H5)2S + 2eam- + NH3 → C2H5S- + C2H6 + NH2- Unit 10 Nomenclature of Hydrocarbons I. Comprehension 1.C 2.D 3.B 4.A 5.B 6.B II. Name the following compounds by the IUPAC system 1 CH3(CH2)nCH3 (n=2, 3, 4, 6, respectively) butane, pentane, hexane, octane 2 (CH3)2-CH2-CH2-CH2-CH3 2-methylpentane 3 (CH3)3C-CH2-CH(C2H5)-CH2-CH3 4-ethyl-2,2-dimethylhexane 4 (CH3)2CH-CH2CH2-CH(CH2CH2CH3)-CH(CH3)2 5-isopropyl-2-methyloctane 5 CH3-CH2-CH2-C(CH2CH2CH3)2-CH(CH3)2 4-isopropyl-4-propylheptane 6 ◇-CH2-CH(CH3)2 isobutylcyclobutane 7 CH2=C(C2H5)(CH(CH3)2) 2-ethyl-3-methyl-1-butene 8 CH3-CH2-CH=CH-CHCl-CH3 2-chloro-3-hexene 9 CH3-CH(CH3)-CH(C2H5)-C≡C-CH3 4-ethyl-5-methyl-2-hexyne 10 CH2=CH-C≡CH 1-buten-3-yne 11 (CH3)2CH-CH2CH(OH)CH3 4-methyl-2-pentanol 12 CH3CH2CH=CHCH(OH)CH3 3-hexen-2-ol 13 (CH3)3C-OH 2-methyl-2-propanol 14 (CH3)3C-OCH2H5 2-ethoxy-2-methylpropane 15 (CH3)2CH-CH2-O-C2H5 1-ethoxy-2-methylpropane 16 (CH2OH)2 1,2-ethanediol 17 CH3-CH(OH)-CH2(OH) 1,2-proanediol 18 CH2(OH)-CH(OH)-CH2(OH) 1,2,3-propanetriol 19 CH3CH2NH2 aminoethane 20 CH3CH2CH2CH(CH3)CH-NH-CH3 N-methyl-1-amino-2-methylpentane III. Draw structures for the following compounds. 1 3-octene C-C-C=C-C-C-C-C 2 3-methy-2-heptene 3 cyclohexene 4 2-pentyne C-CC-C-C 5 3,3-dimethylhexyne 6 3-bromotoluene 7 vinyl chloride C=C-Cl 8 acetylene CC 9 para-dichlorobenzene 10 m-chlorobromobenzene 11 toluene 12 chlorobenzene 13 1,2-dibromobenzene 14 naphthalene 15 anthracene 16 phenanthrene 17 2-methyl-1-propanol 18 Cyclohexanol 19 Methoxyethene 20 trans-2-ethoxycyclohexanol IV. Decide which item best completes each unfinished sentence. 1.A 2.A 3.B 4.C V. Each of the following names is incorrect. Draw the structure represented by the incorrect name (or a consistent structure if the name is ambiguous), and give your drawing the correct name. (…………) Unit 11 Carboxylic Acids and Their Derivatives I. Comprehension 1.B 2.B 3.C 4.D 5.A 6.C II. Fill in the blanks with the phrases given below. 1.brought out 2.dozen or so; put together 3.are made of ;divided by 4.are different from 5.on the contrary; consist of 6.summed up 7.stand for 8.such as 9.are; dependent on 10.break down into III. Put in proper prepositions or adverbs into the blanks. 1.with; as 2.to 3.about 4.from 5.into IV. Translation 1. Similarly, solvent also may not be liquid matter but the others 2. A graph plotting solubility against temperature is called a solubility curve. ( The curve plot drawn (made / produced) by solubility as one coordinate and temperature as another coordinate is called solubility curve.) 3. Air is mixture of gases , the most abundant of which is nitrogen in the form of N2 (molecules). 4. The direction of the reaction and the position of the equilibrium may also be affected by the temperature, pressure, and other conditions. 5. Hydrogen has a great affinity for oxygen and easily combines with it to form water. V. Translation 玻意爾（Bohr）模型提出不久后，人們就發(fā)現(xiàn)原子中的電子比Bohr提出的模型要復(fù)雜得多。實(shí)驗(yàn)證實(shí)電子既有粒子的性質(zhì)（質(zhì)量）也有光的特性（波的特性）。因?yàn)樗膬芍匦?，電子不能被看作是在確定范圍內(nèi)繞核旋轉(zhuǎn)的一種簡單粒子，而且如Bohr所說的，如果電子高速運(yùn)動，我們就不能確切地知道它的位置。 Unit 13 Ultraviolet and Visible Molecular Spectroscopy I. Comprehension 1.C 2.D 3.D 4.D 5.B II. Fill in the blanks of; as; in; out; In; for; for ; of; in; then; to; for;since(for) ; into. III. Fill the blank in each sentence with an appropriate phrase in its proper form. 1. account for 2.take part in 3.think of ….as 4.As compared with 5. is attached to 6.on the contrary 7.As in the case of 8.in contrast with as against 9. owing to 10.Except for. Unit 17 Crystallisation I. Comprehension 1.D 2.A 3.A 4.D 5.A II. Fill in the blanks with the proper word given below. Stage; interna; symmetrical; basis; physical; Furthermore; composed; responsible; reasonable; overall. III. Choose the item from (1) ~ (6) that best matches the item in(a) ~ (f) to make a correct sentence. 1~a; 2~b; 3~c; 4~d; 5~e; 6~f VI.Translate the following into Chinese 共沸物；類質(zhì)同晶；過飽和；砷酸鹽；晶核；異丙基；醇；鈉；硫酸鹽；間甲酚；糖膏； 十水合物；結(jié)晶質(zhì)的；同系物；衍生物；結(jié)晶；四硼酸鹽；鹽析；乙基乙酰苯胺；礦物油。 Uint18 Distillation I. Comprehension 1.B 2.D 3.A 4. A II. Fill in the blanks with the phrases given below. 1.In order to 2.in relation to 3. in the case of 4.in the end 5. in a number of 6.lead to 7.a messy way 掌握以下詞匯: flashdistillation閃蒸 ;exit stream 出流 ;equilibrium curve 平衡曲線; weir 堰; redistillation 重蒸; apparatus 設(shè)備;overhead product 塔頂產(chǎn)物; enthalpy 焓; intersection 交點(diǎn); auxiliary輔助裝置; rectifying section精餾段 ;reflux回流; reboller 再沸器; stripping section 汽提（提餾）段;bottom product 塔底產(chǎn)物 Unit 21 catalysis I. Comprehension 1.A 2.D 3.D 4. B 5.C IV. Translate the following sentences into English (1) We define activity as size (measure) of catalysis of catalyst (2) catalytic reaction may be carried out in different phases, of which mechanisms are generally consistent (3) Enzymes are the most efficient proteins in the human body which accelerate the metabolism of the human body. V. Translate the following into English reaction equilibrium; repetitiveness; elementary reaction step; stability; catalytic cycle; activity; quantitative analysis; selectivity; metabolic reaction; chemical energy; reaction mechanism; polymer nylon（or nylon）;qualitative analysis; molecular-sieve; tubular reactor; inhibitor; stoichiometry. Unit 22 Cosmetics introduction I. Comprehension 1.D 2.A 3.D 4. D 5. (1)True; (2)True; (3) False. II. Fill in the blanks with the proper word given below. Focused on; considerations; particular; boosting; price; affect; commitment; different; proposed. III. Put in proper prepositions or adverbs into the blanks. 1. for, of; 2. to; 3. for 4. for(to) 5. of ,about. V、Translate the following into English. 對亞苯基二胺，降解，丙烯，頭皮屑，洗劑， N-亞硝基二乙醇胺，致癌的， 未成熟（or早熟），香波（or洗發(fā)劑）， 激素（荷爾蒙）， 防汗劑， 誘變性， 脫臭劑（芳香劑）， 推論（必然結(jié)果）， 甘油 VI、Translate the following sentences into English surfactant；environmental pollution；emulsifier；side-effect；dirt；detergent； perspiration；preservative. PART TWO THE FUNDATIONS OF CHEMISTRY Unit7Chemical Bonds 化學(xué)鍵 There are approximately 100 chemical elements. 世界上大概有100種元素。 There are millions of chemical compound, and about 600000 new compounds are prepared every year. 現(xiàn)有數(shù)百萬種化合物，而且每年有60萬種新化合物被合成出來。 To form these compounds, atoms of different elements must be held together in specific combinations. be held together in specific combinations 以特定的方式 為了合成這些化合物，不同種類的原子必須以特定方式結(jié)合在一起。 Chemical bonds are the forces that maintain these arrangements. That引導(dǎo)定語從句，修飾forces 化學(xué)鍵是保持這種結(jié)合狀態(tài)的力。 Chemical bonding also plays a role in determining the state of matter. plays a role 起作用 化學(xué)鍵同時(shí)在決定物質(zhì)狀態(tài)方面也起作用。 At room temperature, water is a liquid, carbon dioxide is a gas, and table salt is a solid because of differences in chemical bonding. 在室溫下，水是液體，二氧化碳是氣體，晶體鹽是固體，是由于化學(xué)鍵的不同。 As scientists developed an understanding of the nature of chemical bonding, they gained the ability to manipulate the structure of compounds. As引導(dǎo)原因狀語從句 to manipulate the structure of compounds不定式短語做賓補(bǔ) 隨著化學(xué)家對化學(xué)鍵認(rèn)識的發(fā)展，他們獲得了控制化合物結(jié)構(gòu)的能力。 Dynamite, birth control pills, synthetic fibers, and a thousand other products were fashioned in chemical laboratories and () have dramatically changed the way we live. 炸藥、避孕藥、合成纖維，和數(shù)以千計(jì)的其他產(chǎn)品在實(shí)驗(yàn)室中被合成出來，并且魔術(shù)般的改變了我們的生活。 We are now entering an era that promises (some would say forebodes) even greater change. 我們現(xiàn)在進(jìn)入了一個(gè)可望（或者說預(yù)言）更大變化的時(shí)代。 The DNA molecular—— the chemical basis of heredity —— carries its genetic message in its bonds in DNA. 分子DNA——遺傳物質(zhì)的基礎(chǔ)——以它的鍵傳遞遺傳信息。 Whether an organism is fish, fowl, hippopotamus, or human is determined by the arrangement of bonds in DNA. Whether an organism is fish, fowl, hippopotamus, or human做主語 無論一個(gè)生物體是魚、家禽、河馬還是人，都是由于DNA的鍵的組合方式?jīng)Q定的。 Scientists already have the ability to rearrange these bonds, and this ability has given them limited control over the structure of living matter. Them, limited control over the structure of living matter雙賓語 科學(xué)家已經(jīng)獲得了重組這些鍵的能力，而這種能力給了他們有限的對生物體結(jié)構(gòu)的控制。 As techniques of genetic engineering improve, scientists may literally be able to custom-tailor genes. 隨著基因工程的發(fā)展，科學(xué)家們將最終設(shè)計(jì)出符合條件的基因。 Let us begin our consideration of chemical bonding so that we, too, can understand the forces that control the structure of matter, living and nonliving. That引導(dǎo)定語從句修飾forces， living and nonliving，動名詞，matter得同位語，修飾matter 讓我們開始對化學(xué)鍵的論述，并由此理解控制物質(zhì)，包括有生命體和無生命體，的結(jié)構(gòu)的力。 Ionic Bond 離子鍵 Let us look at an atom of the element sodium (Na). 我們看一下鈉原子。 It has 11 electrons, of which two are in the first energy level, eight in the second, and one in the third. the first energy level第一能級 the second energy level第二能級 the third energy level第三能級 It has 11 electrons, of which two are in the first energy level, eight are in the second energy level, and one is in the third energy level. 它有11個(gè)電子，其中2個(gè)電子在第一能級，8個(gè)電子在第二能級，1個(gè)電子在第三能級。 If the sodium atom could get rid of an electron, then the product, called a sodium ion, would have the same electron structure as an atom of the noble gas neon (Ne). called a sodium ion 分詞短語做非限定，修飾product noble gas 如果鈉原子能夠失去1個(gè)電子，產(chǎn)物稱為鈉離子，就和惰性氣體氖（Ne）具有相同的電子結(jié)構(gòu)。 Let us immediately emphasize that the sodium ion (Na+) and neon atom (Ne) are not identical. 讓我們首先強(qiáng)調(diào)一下，鈉離子（Na＋）和氖原子（Ne）并不相同。 The electron arrangement is the same, but the nuclei—— and resulting charges—— are not. electron arrangement 電子排布 resulting charges最終電荷 電子排布是相同的，而核及最終電荷是不同的。 As long as sodium keeps its 11 protons, it is still a form of sodium, but it is the sodium ion, not the sodium atom. 只要鈉帶有11個(gè)質(zhì)子，它就一直是鈉，但它是鈉離子而不是鈉原子。 Ions are charged particles, particles in which the number of electrons does not equal the number of protons. in which 引導(dǎo)非限定定語從句。 離子是一種帶電粒子，一種電子數(shù)不等于質(zhì)子數(shù)的粒子。 Positively charged ions are called cations (pronounced “cat-ions”). The sodium ion is a cation. 帶正電荷的粒子稱為陽離子（音為陽－離子）。鈉離子是陽離子。 If a chlorine atom (Cl) could gain an electron, it would have the same electron structure as the noble gas argon (Ar). 如果氯原子（Cl）能夠得到一個(gè)電子，它將與惰性氣體氬（Ar）具有相同的電子結(jié)構(gòu)。 The chlorine atom, having gained an electron, becomes negatively charged. It has 17 protons (17+) and 18 electrons (18-). It is written Cl- and it called a chloride ion. having gained an electron動名詞形式做定語，修飾chlorine atom 獲得一個(gè)電子的氯原子帶有負(fù)電荷。它具有17個(gè)質(zhì)子（17+）和18個(gè)電子（18－），寫作Cl－，稱為氯離子。 Negatively charged ions are called anions (pronounced “ann-ions”). The chloride ion is an anion. 帶負(fù)電荷的粒子稱為陰離子（音為陰－離子）。鈉離子是陰離子。 A sodium forms a less reactive species, a sodium ion, by losing an electron. a less reactive species, a sodium ion同位語 鈉原子通過失去一個(gè)電子形成不活潑的鈉離子。 A chlorine atom becomes a less reactive chloride ion by gaining an electron. 氯原子通過得到一個(gè)電子形成不活潑的氯原子。 A chlorine atom cannot just pluck an electron from empty space, nor can a sodium atom kick out an electron unless something else is willing to take it on. empty space 空白空間、真空空間，意為“憑空”、“無根據(jù)” nor作連詞，與助動詞和情態(tài)動詞連用，句中主語與動詞倒置。 He can’t see, nor could he hear until a month ago. 他現(xiàn)在看不見，一個(gè)月之前他還聽不見。 She isn’t rich, nor do I image that she ever will be. 她現(xiàn)在不富，我看她將來也富不了。 kick out 逐出、解雇、開除；意為“失去” They kicked him out (of the club) for fighting.他因?yàn)槎窔婚_除（出俱樂部）。 something else 別的東西 take … on 接納、承受 氯原子不能憑空獲得一個(gè)電子，而鈉原子也不能憑空失去一個(gè)電子，除非別的東西愿接受電子。 What happens when sodium come into contact with chlorine? The obvious. A chlorine atom removes an electron from a sodium atom. come into contact 接觸、相遇 The obvious 顯而易見的 當(dāng)鈉與氯接觸時(shí)發(fā)現(xiàn)了什么？很明顯，氯原子從鈉原子處拿走了一個(gè)電子。 The sodium ion and the chloride ion have electron arrangements (electron configurations) like those of two noble gases (neon and argon, respectively). electron arrangement電子排布 electron configurations電子結(jié)構(gòu) 鈉離子和氯離子的電子排布（電子結(jié)構(gòu)）就象兩個(gè)惰性氣體（氖和氬，相應(yīng)的）一樣。 Not only do the ions have stable octets of electrons, they also have opposite charges. 它們具有穩(wěn)定的電子八耦體結(jié)構(gòu)，而且有相反的電荷。 Everyone knows that opposites attract. 每個(gè)人都知道異性相吸。 While this rule of thumb may not always work when applied to people, it works quite well for cations and anions. rule of thumb單憑經(jīng)驗(yàn)來做的方法，比較粗糙的方法，約略得衡量（或估計(jì)） 雖然這種經(jīng)驗(yàn)對人未必適用，但對陰陽離子是非常適用的。 The attractive force between oppositely charged ions is called an ionic bond, and the combination of sodium ions and chloride ions is the compound sodium chloride or table salt. 相反電荷之間的吸引力稱為離子鍵，鈉離子和氯離子結(jié)合為化合物氯化鈉和食鹽。 Covalent Bonds共價(jià)鍵 One might expect a hydrogen atom, with its one electron, to acquire another electron and assume the helium configuration. to acquire another electron and (to) assume the helium configuration不定式做賓補(bǔ) 人們也許希望帶有一個(gè)電子的氫原子，獲得另一個(gè)電子并呈現(xiàn)氦的結(jié)構(gòu)。 Indeed, hydrogen atom do just that in the presence of atoms of a reactive metal such as lithium, that is, a metal that finds it easy to give up an electron. do代替上句, just that引導(dǎo)條件狀語 reactive metal活潑金屬 that is 插入語，也就是說 a metal，reactive metal的同位語， that引導(dǎo)定語從句修飾a metal 實(shí)際上，氫原子只有在活潑金屬如鋰的存在下確實(shí)發(fā)生了這樣的反應(yīng)，活潑金屬就是很容易失去電子的金屬。 But what if there are no other kinds of atoms around? 但是，如果周圍沒有其他種類的原子呢？ What if there are only hydrogen atoms (as in a sample of the pure element)? 如果只有氫原子（作為純元素樣品）呢？ One hydrogen atoms can scarcely grab an electrons from another, for among hydrogen atoms all have equal attraction for electrons (Even more important, perhaps, hydrogen atoms do not have a tendency to lose electrons at all, for the result would be a highly reactive bare proton—— the hydrogen nucleus.) Even more important更重要的 一個(gè)氫原子幾乎不能從另一個(gè)氫原子處獲取電子，因?yàn)闅湓泳哂邢嗤碾娮游Γǜ匾?，可能是，氫原子沒有失去電子的傾向，因?yàn)槟菢拥慕Y(jié)果是生成高度活潑的裸露質(zhì)子——?dú)湓雍耍? Still—— hydrogen wants a duet of electrons like helium’s. 而且——?dú)湓酉Ｍ蠛ぴ幽菢訐碛?個(gè)電子。 If one hydrogen cannot capture another’s electron, the two atoms can compromise by sharing their electrons. 如果一個(gè)氫原子不能獲取另一個(gè)氫原子的電子，這兩個(gè)原子則通過共用電子的方式解決。 It is as if the two hydrogen atoms, in approaching one another, get their electron clouds or orbitals so thoroughly enmeshed that they cannot easily pull them apart again. in approaching one another 做插入語 as if與as though 用法相同，意為：宛如、仿佛、好像。as if后面常用過去時(shí)表示現(xiàn)在，說明所作的比較“不是真的”。 You look as if you’d seen a ghost. 在非正式文體中，常用like代替as if。 He sat there smiling like it was his birthday. 就好像兩個(gè)氫原子，當(dāng)它們互相接近時(shí)，其電子云充分重疊，以至于難于再分開。 Moat of the time the electrons are located between the two nuclei. 大部分時(shí)間電子位于兩個(gè)原子之間。 The electron-dot formula usually use