什么是电负性?亲和性又是什么?It is still blur-blur,not clear eno

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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 plete..
Chemical Affinity
Chemical Affinity
, the name given to the force which bines together chemical elements so as to form pounds. 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 e nearer together when they bine: 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 bining as to occupy but two thirds of their former space. In other cases, however, pounds are found to occupy exactly the same space that their elements did before bination, 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 pound 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 bine chemically, both elements disappear, lose their properties and identity, and a new pound is form