2024年2月16日发(作者：)

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

化学是三种基础自然科学之一，另外两种是物理和生物。自从宇宙大爆炸以来，化学过程持续进行，甚至地球上生命的出现可能也是化学过程的结果。人们也许认为生命是三步进化的最终结果,第一步非常快,其余两步相当慢。这三步是：（I）物理进化（化学元素的产生），（II）化学进化（分子和生物分子的形成）；和（III）生物进化（有机物的形成和发展）。

V. Solution:

（1）The relative mass of

1H and

12C atoms can be calculated from their absolute

masses in grams.

H1.673510240.083986

12C1.992610231

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.

kloglog0.6931.21104/yr5730yrA0Akt2.30341.0001.2110/yrt0.4772.3032.303log2.096.11036100yrt1.21104/yr

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

Fe2O3

Sn(OH)2

Sn(OH)4

Hg2SO4

HgSO4

NaCLO

K2Cr2O7

Cu3(AsO4)2

Cr(C2H3O2)3

iron (II) oxide

iron (III) oxide

tin(II) hydroxide

tin(IV) hydroxide

mercury (I) sulfate

mercury (II) sulfate

sodium hypochlorite

potassium dichromate

copper(II) arsenate

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.

altered; illustrate tes expect cancel

6. are pulled on ; referred 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:

OHCOHO+CNHCO+HCNformicacidstrongeracidcyanidestrongerbaseformateweakerbaseweakeracid

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

4

5

6

7

8

9

10

11

12

(CH3)3C-CH2-CH(C2H5)-CH2-CH3

(CH3)2CH-CH2CH2-CH(CH2CH2CH3)-CH(CH3)2

CH3-CH2-CH2-C(CH2CH2CH3)2-CH(CH3)2

◇-CH2-CH(CH3)2

CH2=C(C2H5)(CH(CH3)2)

CH3-CH2-CH=CH-CHCl-CH3

CH3-CH(CH3)-CH(C2H5)-C≡C-CH3

CH2=CH-C≡CH

(CH3)2CH-CH2CH(OH)CH3

CH3CH2CH=CHCH(OH)CH3

4-ethyl-2,2-dimethylhexane

5-isopropyl-2-methyloctane

4-isopropyl-4-propylheptane

isobutylcyclobutane

2-ethyl-3-methyl-1-butene

2-chloro-3-hexene

4-ethyl-5-methyl-2-hexyne

1-buten-3-yne

4-methyl-2-pentanol

3-hexen-2-ol

13

14

15

16

17

18

19

20

(CH3)3C-OH

(CH3)3C-OCH2H5

(CH3)2CH-CH2-O-C2H5

(CH2OH)2

CH3-CH(OH)-CH2(OH)

CH2(OH)-CH(OH)-CH2(OH)

CH3CH2NH2

CH3CH2CH2CH(CH3)CH-NH-CH3

2-methyl-2-propanol

2-ethoxy-2-methylpropane

1-ethoxy-2-methylpropane

1,2-ethanediol

1,2-proanediol

1,2,3-propanetriol

aminoethane

N-methyl-1-amino-2-methylpentane

III. Draw structures for the following compounds.

C-C-C=C-C-C-C-C

1

3-octene

2

3-methy-2-heptene

3

cyclohexene

C-CC-C-C

4

5

2-pentyne

3,3-dimethylhexyne

6

3-bromotoluene

CH3Br

7

8

9

vinyl chloride

acetylene

para-dichlorobenzene

C=C-Cl

CC

Cl10

m-chlorobromobenzene

BrCl

Cl

11

toluene

CH3

12

chlorobenzene

Cl

13

1,2-dibromobenzene

BrBr

14

naphthalene

15

anthracene

16

phenanthrene

17

2-methyl-1-propanol

CCCOHC

18

Cyclohexanol

OH

19

20

Methoxyethene

trans-2-ethoxycyclohexanol

CCOC

OHOC2H5

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.

t out or so; put together made of ;divided by

different from the contrary; consist of up for

as ; dependent on down into

III. Put in proper prepositions or adverbs into the blanks.

; as

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

玻意尔（Bohr）模型提出不久后，人们就发现原子中的电子比Bohr提出的模型要复杂得多。实验证实电子既有粒子的性质（质量）也有光的特性（波的特性）。因为它的两重性，电子不能被看作是在确定范围内绕核旋转的一种简单粒子，而且如Bohr所说的，如果电子高速运动，我们就不能确切地知道它的位置。

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 part in of ….as compared with

5. is attached to the contrary in the case of contrast with

as against 9. owing to 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

ate the following into Chinese

共沸物；类质同晶；过饱和；砷酸盐；晶核；异丙基；醇；钠；硫酸盐；间甲酚；糖膏；

十水合物；结晶质的；同系物；衍生物；结晶；四硼酸盐；盐析；乙基乙酰苯胺；矿物油。

Uint18 Distillation

I. Comprehension

1.B 2.D 3.A 4. A

II. Fill in the blanks with the phrases given below.

order to relation to 3. in the case of the end

5. in a number of to 7.a messy way

掌握以下词汇:

flashdistillation闪蒸 ;exit stream 出流 ;equilibrium curve

平衡曲线;

weir 堰;

redistillation

重蒸; apparatus

设备;overhead product 塔顶产物;

enthalpy 焓;

intersection

交点;

auxiliary辅助装置;

rectifying section精馏段 ;reflux回流;

reboller

再沸器;

stripping section

汽提（提馏）段;bottom product

塔底产物

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.

对亚苯基二胺，降解，丙烯，头皮屑，洗剂， N-亚硝基二乙醇胺，致癌的， 未成熟（or早熟），香波（or洗发剂）， 激素（荷尔蒙）， 防汗剂， 诱变性，

脱臭剂（芳香剂）， 推论（必然结果）， 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

化学键

There are approximately 100 chemical elements.

世界上大概有100种元素。

There are millions of chemical compound, and about 600000

new compounds are prepared every year.

现有数百万种化合物，而且每年有60万种新化合物被合成出来。

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

为了合成这些化合物，不同种类的原子必须以特定方式结合在一起。

Chemical bonds are the forces that maintain these arrangements.

That引导定语从句，修饰forces

化学键是保持这种结合状态的力。

Chemical bonding also plays a role in determining the state of

matter.

plays a role 起作用

化学键同时在决定物质状态方面也起作用。

At room temperature, water is a liquid, carbon dioxide is a gas,

and table salt is a solid because of differences in chemical bonding.

在室温下，水是液体，二氧化碳是气体，晶体盐是固体，是由于化学键的不同。

As scientists developed an understanding of the nature of

chemical bonding, they gained the ability to manipulate the structure

of compounds.

As引导原因状语从句

to manipulate the structure of compounds不定式短语做宾补

随着化学家对化学键认识的发展，他们获得了控制化合物结构的能力。

Dynamite, birth control pills, synthetic fibers, and a thousand

other products were fashioned in chemical laboratories and () have

dramatically changed the way we live.

炸药、避孕药、合成纤维，和数以千计的其他产品在实验室中被合成出来，并且魔术般的改变了我们的生活。

We are now entering an era that promises (some would say

forebodes) even greater change.

我们现在进入了一个可望（或者说预言）更大变化的时代。

The DNA molecular—— the chemical basis of heredity ——

carries its genetic message in its bonds in DNA.

分子DNA——遗传物质的基础——以它的键传递遗传信息。

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做主语

无论一个生物体是鱼、家禽、河马还是人，都是由于DNA的

键的组合方式决定的。

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双宾语

科学家已经获得了重组这些键的能力，而这种能力给了他们有限的对生物体结构的控制。

As techniques of genetic engineering improve, scientists may

literally be able to custom-tailor genes.

随着基因工程的发展，科学家们将最终设计出符合条件的基因。

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引导定语从句修饰forces，

living and nonliving，动名词，matter得同位语，修饰matter

让我们开始对化学键的论述，并由此理解控制物质，包括有生命体和无生命体，的结构的力。

Ionic Bond 离子键

Let us look at an atom of the element sodium (Na).

我们看一下钠原子。

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第一能级

the second energy level第二能级

the third energy level第三能级

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个电子，其中2个电子在第一能级，8个电子在第二能级，1个电子在第三能级。

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 分词短语做非限定，修饰product

noble gas

如果钠原子能够失去1个电子，产物称为钠离子，就和惰性气体氖（Ne）具有相同的电子结构。

Let us immediately emphasize that the sodium ion (Na+) and

neon atom (Ne) are not identical.

让我们首先强调一下，钠离子（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 电子排布

resulting charges最终电荷

电子排布是相同的，而核及最终电荷是不同的。

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.

只要钠带有11个质子，它就一直是钠，但它是钠离子而不是钠原子。

Ions are charged particles, particles in which the number of

electrons does not equal the number of protons.

in which 引导非限定定语从句。

离子是一种带电粒子，一种电子数不等于质子数的粒子。

Positively charged ions are called cations (pronounced

“cat-ions”). The sodium ion is a cation.

带正电荷的粒子称为阳离子（音为阳－离子）。钠离子是阳离子。

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）能够得到一个电子，它将与惰性气体氩（Ar）具有相同的电子结构。

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动名词形式做定语，修饰chlorine

atom

获得一个电子的氯原子带有负电荷。它具有17个质子（17+）和18个电子（18－），写作Cl，称为氯离子。

Negatively charged ions are called anions (pronounced

“ann-ions”). The chloride ion is an anion.

带负电荷的粒子称为阴离子（音为阴－离子）。钠离子是阴离子。

A sodium forms a less reactive species, a sodium ion, by losing

an electron.

a less reactive species, a sodium ion同位语

钠原子通过失去一个电子形成不活泼的钠离子。

A chlorine atom becomes a less reactive chloride ion by gaining

an electron.

氯原子通过得到一个电子形成不活泼的氯原子。

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 空白空间、真空空间，意为“凭空”、“无根据”

nor作连词，与助动词和情态动词连用，句中主语与动词倒置。

He can’t see, nor could he hear until a month ago. 他现在看不－

见，一个月之前他还听不见。

She isn’t rich, nor do I image that she ever will be. 她现在不富，我看她将来也富不了。

kick out 逐出、解雇、开除；意为“失去”

They kicked him out (of the club) for fighting.他因为斗殴而被开除（出俱乐部）。

something else 别的东西

take … on 接纳、承受

氯原子不能凭空获得一个电子，而钠原子也不能凭空失去一个电子，除非别的东西愿接受电子。

What happens when sodium come into contact with chlorine?

The obvious. A chlorine atom removes an electron from a sodium

atom.

come into contact 接触、相遇

The obvious 显而易见的

当钠与氯接触时发现了什么？很明显，氯原子从钠原子处拿走了一个电子。

The sodium ion and the chloride ion have electron arrangements

(electron configurations) like those of two noble gases (neon and

argon, respectively).

electron arrangement电子排布

electron configurations电子结构

钠离子和氯离子的电子排布（电子结构）就象两个惰性气体（氖和氩，相应的）一样。

Not only do the ions have stable octets of electrons, they also

have opposite charges.

它们具有稳定的电子八耦体结构，而且有相反的电荷。

Everyone knows that opposites attract.

每个人都知道异性相吸。

While this rule of thumb may not always work when applied to

people, it works quite well for cations and anions.

rule of thumb单凭经验来做的方法，比较粗糙的方法，约略得衡量（或估计）

虽然这种经验对人未必适用，但对阴阳离子是非常适用的。

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.

相反电荷之间的吸引力称为离子键，钠离子和氯离子结合为化合物氯化钠和食盐。

Covalent Bonds共价键

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不定式做宾补

人们也许希望带有一个电子的氢原子，获得另一个电子并呈现氦的结构。

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引导条件状语

reactive metal活泼金属

that is 插入语，也就是说

a metal，reactive metal的同位语，

that引导定语从句修饰a metal

实际上，氢原子只有在活泼金属如锂的存在下确实发生了这样的反应，活泼金属就是很容易失去电子的金属。

But what if there are no other kinds of atoms around?

但是，如果周围没有其他种类的原子呢？

What if there are only hydrogen atoms (as in a sample of the pure

element)?

如果只有氢原子（作为纯元素样品）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

一个氢原子几乎不能从另一个氢原子处获取电子，因为氢原子具有相同的电子吸引力（更重要的，可能是，氢原子没有失去电子的倾向，因为那样的结果是生成高度活泼的裸露质子——氢原子核）。

Still—— hydrogen wants a duet of electrons like helium’s.

而且——氢原子希望象氦原子那样拥有2个电子。

If one hydrogen cannot capture another’s electron, the two atoms

can compromise by sharing their electrons.

如果一个氢原子不能获取另一个氢原子的电子，这两个原子则通过共用电子的方式解决。

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 做插入语

as if与as though 用法相同，意为：宛如、仿佛、好像。as if后面常用过去时表示现在，说明所作的比较“不是真的”。

You look as if you’d seen a ghost.

在非正式文体中，常用like代替as if。 He sat there smiling like

it was his birthday.

就好像两个氢原子，当它们互相接近时，其电子云充分重叠，以至于难于再分开。

Moat of the time the electrons are located between the two

nuclei.

大部分时间电子位于两个原子之间。

The electron-dot formula usually used, H:H, is therefore a fairly

good picture (If we were to attribute human qualities to hydrogen

atoms, we would suggest that they are a bit nearsighted. Each one

looks around, sees two electrons, and decides that these electrons are

its very own and that therefore it has as arrangement like that of

helium, one of the noble gases.)

electron-dot formula 电子式

noble gase惰性气体

经常用电子式H：H表示，这是一个很好的画面（如果我们以人的品性归于氢原子，我们说它们有些目光短浅。每个氢原子看看周围，看到两个电子，就认为这些电子是自己的，它们就有了象惰性气体氦那样的电子排布）。

This combination of hydrogen atoms is called a hydrogen

molecule.

这种氢原子化合物叫氢分子。

Molecules are discrete groups of atoms held together by shared

pairs of electrons. The bond formed by a shared pair of electrons is

called a covenlent bond.

分子是通过共用电子对将两个分离的原子结合在一起。通过共用电子对形成的键称为共价键。

A chlorine atom will pick up an extra electron from anything

willing to give one up.

氯原子可以从任何愿意失去一个电子的原子处得到一个电子。

But, again, what if the only thing around is another chlorine

atom?

但是，如果周围只有另一个氯原子又会怎样？

Chlorine atoms, too, can attain a more stable arrangement by

sharing a pair of electrons.

氯原子同样也是通过共用电子对达到稳定结构。

Each chlorine atom in the chlorine molecule counts eight

electrons around itself and concludes that it has an arrangement like

that of the noble gas argon.

that it has an arrangement like that of the noble gas argon.宾语从句

氯分子中每个氯原子周围都有8个电子，并且可以断定它具有惰性气体氩一样的排布。

The shared pair of electrons in the chlorine molecule also creates

a covalent bond.

氯分子中共用的一对电子同样形成共价键。

For simplicity, the hydrogen molecule is often represented as H2

and the chlorine molecule as Cl2.

the chlorine molecule as Cl2：the chlorine molecule is often

represented as Cl2

为了简化，氢分子常写成H2，氯分子常写成Cl2。

The subscripts indicate two atoms per molecule.

这个下标表示每个分子中有2个原子。

In each case, the covalent bond between the atoms is understood.

Sometimes the covalent bond is indicated by a dash, H-H and Cl-Cl.

在每种情况下，原子之间的共价键都可以理解，有时共价键也用一个短线表示H－H和Cl－Cl。：

Let us be sure we understand the meaning of numbers in

formulas.

让我们确信我们理解公式中数字的意义。

Take a moment to establish in your mind the difference among

the following: H，H2，2H，2 H2，H2O，2 H2O.

花点时间来搞清楚下面数字的不同：H，H2，2H，2 H2，H2O，2

H2O。

Is it clear to you that although H represents a single atom of

hydrogen, H2 implies two atoms of H bonded together, whereas 2H

represents two separate, free, and independent atoms of H?

That引导实际主语

你是否明白H代表分离的氢原子，H2代表两个H结合而成的氢分子，而2H代表分离的、自由的、孤立的氢原子吗？

On the other hand, the meaning of H2 in H2O is totally different

from that of H2 as a molecule.

另一方面， H2在H2O中的意思与作为一种分子的H2完全不同。

In H2O it means that two atoms of H are individually attached to

O（not to themselves!） to form a molecule of water.

在 H2O中表示两个H分别吸引O（而不是它们自己！）来形成一个水分子。

Finally, 2 H2O simply refers to two individual molecules of

water.

最后，2 H2O代表两个独立的水分子。

Covalent bonds are not limited to the sharing of one pair of

electrons. Consider, for example, the nitrogen atom. Its electron-dot

... is：.

...N.式是：.

共价键不限于分享一对电子。例如，对于氮原子。它的电子Now, after all we have learned about the octet rule we know that

this electron arrangement is not complete.

octet rule八耦体规则

现在，我们学习了八耦体规则。我们知道这个电子排布是不饱和的。

It has only five electrons in its outermost energy level.

outermost energy level外层电子能级

在它的外层电子能级上只有5个电子。

..：：：NN..would then look like this：

..：N.：N.：

It could shared a pair of electrons with another nitrogen atom and

它可以与另一个氮原子共用一对电子而变成如下形式：The situation has not improved a great deal.

情况并没有发生太大变化。

Each nitrogen atom in this arrangement has only six electrons

surrouding it (not eight).

每个氮原子周围电子排布只有6个电子（不是8个）。

Each nitrogen atom has two electrons hanging out there without

partners, so, to solve the dilemma, each nitrogen atom shares two

additional pairs of electrons, for a total of three pairs.

hanging out把…伸出、挂出，上身伸出（窗外），闲荡

每个氮原子都有两个未成对电子，所以，为了解决这一矛盾，每个氮原子共用另外两对电子，共3对电子

：..N：N

In drawing the nitrogen molecule (N2), we have placed all the

electrons being shared by the two atoms in the space between the

two atoms.

being shared by the two atoms分词短语做定语

写氮分子（N2）时，我们把两个原子的所有的共用电子都写在两个原子中间。

Each nitrogen atom has now satisfied the octet rule.

每个氮原子都满足了八耦体规则。

A molecule in which three pairs of electrons (a total of six

individual electron) are being shared is said to contain a triple bond.

in which three pairs of electrons (a total of six individual electron)

are being shared定语从句

triple bond三键

一个分子共享三对电子（共6个单个电子）被称为含有三键。

Each nitrogen atom also has an unshared pair of electrons.

每个氮原子还含有一对孤对电子。

Note that we could have drawn the unshared pair of electrons

above or below the atomic symbol.

atomic symbol 元素符号

注意我们可以把孤对电子写在元素符号的上方或下方。

Such a drawing would represent the same molecule.

这些写法代表相同的分子。

Polar Covalent Bonds 极性共价键

So far we have seen that atoms combine in two different ways.

So far迄今为止，就此范围（或程度）说来

迄今为止，我们看到了两种不同的原子结合方式。

Some that are quite different in electron structure (from the

opposite ends of the periodic table) react by the complete transfer of

one or more electrons from one atom to another (ionic bond

formation).

from the opposite ends of the periodic table周期表相对的两端

句子结构：some……react by……

Transfer 名词

那些原子结构截然不同（周期表左右两端）的原子，一个将

一个或数个电子由一个原子完全传递到另一个原子的方式反应（离子键形成）。

Atoms that are identical combine by sharing one or more pairs of

electrons (covalent bond formation).

相同的原子通过共用一对或多对电子（共价键形成）而结合。

Now let us look at some “in-betweeners”.

现在让我们看一下“居于中间者”。

Hydrogen and chlorine react to form a colorless, toxic gas called

hydrogen chloride.

hydrogen chloride 氯化氢

氢与氯反应生成一种无色、有毒的气体氯化氢。

This reaction can be represented schematically by

这个反应可由下式表示：

H ＋ Cl → HCl 或（H－Cl）

Both the hydrogen atom and the chlorine atom want an electron,

so they compromise by sharing and form a covalent bond.

氢原子和氯原子都想得到一个电子，所以它们通过共用电子对结合并形成共价键。

Since the substances hydrogen and chlorine actually consist of

diatomic molecules rather than single atoms, the reaction is more

accurately represented by the scheme.

diatomic molecules 二原子分子

由于氢和氯实际上是二原子分子而不是单个原子，反应写成下式更准确

....H：H＋：Cl..：Cl..：..：Cl：2H..

This can be more simply written as

简写为H2 ＋ Cl2 → 2HCl

One might reasonably ask why the hydrogen molecule and the

chlorine molecule react at all.

有人也许会问为什么氢分子和氯分子能够完全反应。

Have we not just explained that they themselves were formed

provide a more stable arrangement of electrons?

宾语

我们不是已经解释了它们本身形成了相对稳定的电子排布了吗？

Yes, indeed, we say that. But there is stable and there is more

stable.

是的，我们说过这些，但这有稳定和更稳定。

The chlorine molecule represents a more stable arrangement than

separate chlorine atoms, but, given the opportunity, a chlorine atom

would rather bond to hydrogen than（bond）to another chlorine atom.

would rather……than含有选择得意思，“宁可……而不……”

would rather与than后面为平行结构

氯分子代表着比单独的氯原子更稳定的排列，但是，若有机会，氯原子宁可与氢成键而不愿与另一个氯成键。

In a molecule of hydrogen chloride, a chlorine atom shares a pair

of electrons with a hydrogen atom.

在氯化氢分子中，氯原子和氢原子共用一对电子。

In this case, and in others we shall consider, sharing does not

mean sharing equally.

在这种情况下，以及我们能想到的其他情况，共用并不意味着完全分享。

Some atoms within molecules attract electrons more strongly

than do other atoms.

分子中一些原子吸引电子的能力比其他原子强。

The term electronegativity is used to describe the affinity of an

element in a molecule for electrons.

电负性是用来描述分子中原子的亲和力的。

The higher the electronegativity, the more strongly the atoms of

an element attract electrons to themselves.

电负性越大，原子吸引电子的能力越强。

The most electronegativity element is fluorine, which is located

in the upper right corner of the periodic table.

电负性最大的元素是氟，它处于元素周期表的右上角。

The electronegativity of elements decreases as one moves away

from fluorine in the periodic table.

在周期表中，离氟越远，元素的电负性越弱。

Thus electronegativity decreases as one moves down a group

(column) or left across a period (row).

down a group (column) 由族（列）向下

left across a period (row) 由周期（行）向左

所以，由族（列）向下或由周期（行）向左，电负性减弱。

I. Comprehension

1. What is the main idea of the paragraph? A

A. There are so many kinds of chemical bonds.

B. How does the ionic bond come into being.

C. The noble gases are stable.

D. Can sodium atoms and chlorine atoms react with each other

to form a stable arrangement of electrons.

2. What is the author’s meaning by saying “even atoms have their

own standards of beauty”? B

A. Atoms can detect whether an electron arrangement is

beautiful or not.

B. There are standards or rules that can determine if an electron

arrangement is favored or not.

C. Atoms are more favored a beautiful electron arrangement than

an ugly one.

D. We can beautify atoms by their standards.

3. What’s “the standards of beauty” of atoms? C

A. An octet (eight outer electrons).

B. A duet (two outer electrons).

C. A and B.

D. There is no such standards.

4. Are the sodium ion (Na+) and the neon atom (Ne) identical?

E

A. Yes, they have same electron numbers.

B. Yes, they have same electron arrangement.

C. No, sodium ion is still a form of sodium, not atom but cations.

D. No, sodium ion is a charged particle, while the neon atom is a

neutral one.

E. C and D.

5. It is impossible for Tom to judge such important affair B

A. as a rule of thumb.

B. by rule of thumb.

C. though a rule of thumb.

D. by experiment.

6. What happens during Na + Cl Na+Cl- D

A. the nuclei of each ions are changed.

B. the inner energy level of electrons changed.

C. A and B.

D. The outermost energy level is altered.

7. Is there any order or any pattern to the way that the electron dot

are draw? C

A. No, there is no any order.

B. Yes, the p orbitals are filled firstly.

C. Yes, the s orbital is filled firstly and the p orbitals.

D. Yes, but the p orbitals is filled willfully.

V. Translation

Chlorine is more electronegative than hydrogen. In a hydrogen

chloride molecule, the chlorine atom has a much greater attraction

than the hydrogen atom for the shared electron pair. Because the

shared electron are held more tightly by the chlorine atom, the

chlorine end of the molecule is more negative than the hydrogen end.

If you think of an orbital as a fuzzy-looking cloud, then the cloud is

denser near the chlorine atom. When the electrons in a covalent bond

are not equally shared, the bond is said to be polar. Thus the bonding

in hydrogen chloride is described as polar covalent. Whereas the

bonding in the hydrogen molecule or in the chlorine molecule in

nonpolar covalent. The polar covalent bond is not an ionic bond. In

an ionic bond, one atom completely losed an electron. In a polar

covalent bond, the atom at the positive end of the bond (hydrogen in

HCl) still gas some share in the bonding pair of electrons. To

distinguish this arrangement from that in an ionic bond, the

following notation is use.

The line between the atoms represents the covalent bond, a pair

of shared electrons. The δ+ and δ- signify which end is partially

positive and which is partially negative (the word partially is used to

distinguish this charge from the full charge on an ion).

氯比氢的电负性更大。在氯化氢分子中，氯对共用电子对的吸引力比氢更大。由于共用电子对被氯牢牢控制，氯一端的负电性比氢一端更强。如果把轨道想象成云朵，在氯一端云朵的密度更大。当共价键中的电子不是完全分享时，键称为极性键。在氢分子和氯分子中的键为非极性键。极性共价键不是离子键。在极性键中，原子完全失去电子。在极性键中位于正电一端的原子仍然分享共用电子。为了表示与离子键的区别，用下面的图表示。

原子之间的键表示共价键，一对共用电子。δ+和δ-表示带部分正电或部分带负电的一端（部分这个词时为了表示与离子键的不同）。