应用化学专业英语第二版万有志主编版课后答案和课文翻译
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应⽤化学专业英语第⼆版万有志主编版课后答案和课⽂翻译
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.
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.
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 (p K a=3.76) is a stronger acid than HCN (p K a=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 + 2e am-→ H2 + 2CH3GeH2-
(2) I2 + 2e am-→ 2I-
(3) (C2H5)2S + 2e am- + NH3 → C2H5S- + C2H6 + NH2-
Unit 10 Nomenclature of Hydrocarbons
I. Comprehension
1.C
2.D
3.B
4.A
5.B
6.B
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
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;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.
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
掌握以下词汇:
flashdistillation闪蒸;exit stream出流;e quilibrium 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 arrangement s (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 look s around, see s two electrons, and decide s 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, H2implies 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.。