什么是电负性？亲和性又是什么？

电负性和亲和性有什么差别 分别和什么有关？~

1、所有的引力势能都是负的。

A、外星球来的罗敏欧，要救走地球上的朱丽叶，必须付出代价，付出能量；

B、从井底救出一个失足落井之人，井越深，需要付出的能量就会越多；

C、将一个正电荷附近的电子推到无穷远，需要付出能量；

、、、、、、这些都是“负”性的表示，“负性”的特征。



2、电负性 electronegativity，表示元素原子在分子中对成键电子的吸引能力；

元素电负性数值越大，原子在形成化学键时，对成键电子的吸引力就越强。

因此，要把化学键打断
bond-breaking，需要的能量就越大。

3、亲和性 affinity，
是对同一事情，同一现象，同一原理，进行不同的描述，得到的不同说法。

电负性的说法，站在超然的地位，在评价某个原子核、某个原子实、某个离子、、、
有多大的吸引力，、、、、、

亲和性的说法，设身处地地站在化合以后的角色上说话：
我们怎么怎么亲如一家，怎么怎么血肉相连、、、
我们怎么怎么亲和无间，要破坏须付出什么代价。

即使没有化合，也站在化合后的身份、地位、【趋势】谈论：
（请参看英文解释）
A、In chemical physics and physical chemistry, chemical affinity is the electronic property by which dissimilar chemical species are capable of forming chemical compounds.

B、Chemical affinity can also refer to the tendency of an atom or compound to combine by chemical reaction with atoms or compounds of unlike composition.

C、In modern terms, we relate affinity to the phenomenon whereby certain atoms or molecules have the 【tendency】 to aggregate or bond.

electron affinity: 即电子亲和能或电子亲和势（ Eea），定义为单位原子或分子获得一个电子，变成 -1 价离子时放出的能量。对元素来说，电子亲合能越大，夺取电子的能力（或称“非金属性”）越强。

electronegativity: 即电负性，首先由莱纳斯·鲍林于1932年提出，它综合考虑了电离能和电子亲合能，以一组数值的相对大小表示元素原子在分子中对成键电子的吸引能力。元素电负性数值越大，原子在形成化学键时对成键电子的吸引力越强。

两者有关，但不能等同。电子亲和能是可以具体测量的，单位是KJ/mol，电子亲和能最大的元素是氯元素；电负性无单位，其数值除了考虑亲和能，还考虑了电离势，电负性最大的元素是氟元素。（当然，理论电负性最大的是氦元素）

电负性：electronegativity.

电负性（简写 EN），也译作负电性及阴电性，是综合考虑了电离能和电子亲合能，首先由莱纳斯·鲍林于1932年提出。它以一组数值的相对大小表示元素原子在分子中对成键电子的吸引能力，称为相对电负性，简称电负性。元素电负性数值越大，原子在形成化学键时对成键电子的吸引力越强。

同一周期从左至右，有效核电荷递增，原子半径递减，对电子的吸引能力渐强，因而电负性值递增；同族元素从上到下，随着原子半径的增大，元素电负性值递减。过渡元素的电负性值无明显规律。就总体而言，周期表右上方的典型非金属元素都有较大电负性数值，氟的电负性值数大（4.0）；周期表左下方的金属元素电负性值都较小，铯和钫是电负性最小的元素（0.7）。一般说来，非金属元素的电负性大于2.0，金属元素电负性小于2.0。

电负性概念还可以用来判断化合物中元素的正负化合价和化学键的类型。电负性值较大的元素在形成化合物时，由于对成键电子吸引较强，往往表现为负化合价；而电负性值较小者表现为正化合价。在形成共价键时，共用电子对偏移向电负性较强的原子而使键带有极性，电负性差越大，键的极性越强。当化学键两端元素的电负性相差很大时（例如大于1.7）所形成的键则以离子性为主。

元素的电负性愈大，吸引电子的倾向愈大，非金属性也愈强。电负性的定义和计算方法有多种，每一种方法的电负性数值都不同，比较有代表性的有3种：

① 莱纳斯·鲍林提出的标度。根据热化学数据和分子的键能，指定氟的电负性为3.98，计算其他元素的相对电负性。

②R.S.密立根从电离势和电子亲合能计算的绝对电负性。

③A.L.阿莱提出的建立在核和成键原子的电子静电作用基础上的电负性。利用电负性值时，必须是同一套数值进行比较。

常见元素电负性（鲍林标度）

氢 2.2 锂 0.98 铍 1.57 硼 2.04 碳 2.55 氮 3.04 氧 3.44 氟 3.98
钠 0.93 镁 1.31 铝 1.61 硅 1.90 磷 2.19 硫 2.58 氯 3.16
钾 0.82 钙 1.00 锰 1.55 铁 1.83 镍 1.91 铜 1.9 锌 1.65 镓 1.81 锗 2.01 砷 2.18 硒 2.48 溴 2.96
铷 0.82 锶 0.95 银 1.93 碘 2.66 钡 0.89 金 2.54 铅 2.33

亲和性, affinity
化学亲和性指的是使化学元素之间形成化合物所提供的力。

这有些英文接受，不知道你能否看得懂：

This section is from "The American Cyclopaedia", by George Ripley And Charles A. Dana. Also available from Amazon: The New American Cyclopædia. 16 volumes complete..

Chemical Affinity
Chemical Affinity, the name given to the force which combines together chemical elements so as to form compounds. Of its real nature or essence we are entirely ignorant, as we are of the essential nature of other material forces. The term chemical attraction has also been applied to this force, on the hypothesis that it draws together chemical atoms. In many cases there can be no doubt that the chemical particles come nearer together when they combine: thus if two volumes of hydrogen and one volume of oxygen be caused to unite, we do not get three volumes of steam, but only two; that is, the particles have ap-proached so much closer in combining as to occupy but two thirds of their former space. In other cases, however, compounds are found to occupy exactly the same space that their elements did before combination, and sometimes they fill even a greater space. Hence the term chemical attraction has been thought objectionable. Chemical affinity is that link or tie which binds together unlike kinds of matter, in such an intimate manner that the properties of the elements are lost, and a compound with new properties is produced. It is in this that it differs from cohesion, which only unites or aggregates similar particles without altering properties.

The particles in a piece of iron or sulphur are held in union by cohesion; but when sulphur and iron combine chemically, both elements disappear, lose their properties and identity, and a new compound is formed - the sulphuret of iron. Newness of properties in the compounds formed is the distinguishing peculiarity i of chemical affinity. It obliterates the characteristics of the elements, and generates new properties in the product. Cohesion is usually said to act between homogeneous particles, as in the cases just cited of sulphur and iron; but it may also act between dissimilar substances, as where silver is inlaid with steel, or copper metal united to tin, or iron coated with zinc, or wood joined to glue, or paper to paste, or pitch to the fingers. These, however, are mechanical combinations; there is no destruction of the properties of the combined substances, and those of the combination are not new, but are the same as the properties of the constituent substances, each of which retains its individuality. The force of gravitation is brought into play between masses of matter at all distances; chemical affinity acts only when the elements are in contact or at insensible distances.

For this reason affinity is most energetic when one or both of the elements are in a state of solution, the approach of the atoms being then most perfect. It was once thought that chemical affinity could not take effect without the intervention of solution; and although the statement is generally true, yet there are some substances whose affinities are so intense that they will unite even in the solid state when made to touch each other. The action of affinity is heightened, modified, and suspended by various other causes. Among these heat is most potent, and most easily available in the laboratory and chemical manufactory. Thus carbonic acid and lime unite strongly at common temperatures, forming marble or limestone, but at a red heat their affinity is annihi-lated and they separate. On the other hand, potash and sand will not actively combine at ordinary temperatures, while at a red or white heat, at which they are melted, combination takes place and glass is formed. Light also influences affinity, promoting combination and decomposition. If chlorine and hydrogen gases be mixed in the dark they will not unite, but exposed to light they combine at once; while in every green vegetable leaf carbonic acid is decomposed every day under the inthi-ence of solar light.

The recent investigations in photography have greatly multiplied the number of substances over which light is known to exert a chemical influence. Electricity also has a governing action over affinity. An electric spark, shot through a mixture of oxygen and hydrogen gases, causes them to combine instantaneously and explosively, producing water; while a steady electric stream sent through the water annuls the affinity of its elements and sets them free again. Other causes also, known and unknown, affect in various ways and degrees the play of affinity; indeed, a full statement of them would involve almost the whole science of chemistry. - The changes in the properties of substances produced by affinity are numberless and surprising. When solid charcoal and sulphur combine, the compound formed is colorless as water, and highly volatile. If yellow sulphur and bluish white quicksilver be heated together, they form the bright red vermilion. Waxy phosphorus and colorless invisible oxygen unite to form a white body resembling snow. Nitrogen and oxygen are tasteless, separate or mixed; yet one of their compounds, laughing gas, is sweet, and another, nitric acid, intensely sour; they are both transparent and invisible, yet they form a cherry-red compound gas.

Charcoal and hydrogen are odorless; nevertheless, many of our choicest perfumes, such as oils of roses and bergamot, as well as the less agreeable spirits of turpentine and illuminating gas, contain only these elements. The mild and scentless nitrogen and hydrogen give rise to one of the most odorous and pungent compounds, ammonia; while suffocating and poisonous chlorine, united to a bright metal, sodium, yields common salt. Charcoal, hydrogen, and nitrogen, which singly or mixed are not injurious to life, yet combine to form the terrible poison prussic acid; while charcoal, hydrogen, and oxygen, variously united, produce sweet sugar, poisonous oxalic acid, and intoxicating alcohol.- The strength of affinity among different elements is various. Thus the chemical energies of sulphuric acid are superior to those of carbonic acid; if the former be united to carbonate of lime, it takes the lime away from the carbonic acid - that is, produces decomposition and a new compound. It has been attempted to establish a scale of affinities among various chemical substances to form the basis of an order of decomposition; but affinity is disturbed and overcome by so many circumstances that such tables are of but little value.

For the laws of affinity or chemical combination, see Atomic Theory.

＝＝＝＝＝＝＝＝＝
In chemical physics and physical chemistry, chemical affinity can be defined as electronic properties by which dissimilar chemical species are capable of forming chemical compounds.[1] Chemical affinity can also refer to the tendency of an atom or compound to combine by chemical reaction with atoms or compounds of unlike composition.

According to chemistry historian Henry Leicester, the influential 1923 textbook Thermodynamics and the Free Energy of Chemical Reactions by Gilbert N. Lewis and Merle Randall led to the replacement of the term “affinity” by the term “free energy” in much of the English-speaking world.

[edit] Modern conceptions
In modern terms, we relate affinity to the phenomenon whereby certain atoms or molecules have the tendency to aggregate or bond. For example, in the 1919 book Chemistry of Human Life physician George W. Carey states: “Health depends on a proper amount of iron phosphate Fe3(PO4)2 in the blood, for the molecules of this salt have chemical affinity for oxygen and carry it to all parts of the organism.” In this antiquated context, chemical affinity is sometimes found synonymous with the term "magnetic attraction". Many writings, up until about 1925, also refer to a “law of chemical affinity”.

电负性：是以一组数值的相对大小表示元素原子在分子中对成键电子的吸引能力，称为相对电负性，简称电负性。元素电负性数值越大，原子在形成化学键时对成键电子的吸引力越强。

亲和性
〔1〕一般说来其概念有些模糊，但是有时则作为特定的术语使用。例如，在组织学上被视为表示组织对某种染料结合力强的一种术语。另外，在胚胎学上，表示细胞或组织相互连接的意思。在这种情况下，根据其连接倾向是紧密的还是分离的，则分别称之为正、负亲和性。用脱钙或胰蛋白酶处理等方法，可从胚中游离出细胞，从对这些细胞进行的实验中可以获得有关亲和性的资料。

(2〕又称向性。病毒只能在活动状态的活细胞内发育繁殖，而且各种病毒必须在与其相应的某种细胞内才能繁殖，将此称为病毒亲和性（或特称细胞亲和性，或细胞向性）。例如，流感病毒在人和鼷鼠的气管上皮细胞中繁殖，大肠杆菌噬菌体在大肠杆菌中繁殖。

不用弄的那么复杂，电负性就是原子对核外电子的引力。电负性越强，引力越大。电子越不容易失去。亲和性没有什么定向的概念，太笼统了。

用最简单的话来说
电负性就是指原子吸引电子的能力，电负性越大，吸引电子能力越大，也就是氧化性越大。
亲和性指一种物质对另外一种物质能够结合、吸附等相互靠近的性质。

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薛城区19342974575： 什么是电负性 - ？
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