英语翻译since the first publications of the periodic law,both by dimitri mendeleev and lothar meyer in the 1870s,there have been a large number of forms proposed for the periodic table.the version easiest to use and most closely related to the el
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英语翻译since the first publications of the periodic law,both by dimitri mendeleev and lothar meyer in the 1870s,there have been a large number of forms proposed for the periodic table.the version easiest to use and most closely related to the el
英语翻译
since the first publications of the periodic law,both by dimitri mendeleev and lothar meyer in the 1870s,there have been a large number of forms proposed for the periodic table.
the version easiest to use and most closely related to the electronic structures of the atoms is so-called long-form in table 1.
the elements fall into 18 vertical columns that define the chemical families,or
groups.the members of each group have valence-electron configurations that are the same,except for principal numbers.the only exceptions to this rule involve nearby and electrons.
while chemical similarties are most often strongest among elements in same column,there is some resemblance between elements that are not in the same column but which do have the same number of valence electrons.
r example,members of the scandium group have the configuration(n-1)d1ns2 and are in some respects similar to the elements below boron,which have the configurations ns2np1.
consequently the elements under scandium in the third column are said to be members of group iiib ,while the boron family is labeled group iiia.
other groups in the perodic table are related and labeled in asimilar manner.
the elements in the three columns designated group viii resemble each other in many respects and separate the a subgroups from the b subgroups in periodic table.
英语翻译since the first publications of the periodic law,both by dimitri mendeleev and lothar meyer in the 1870s,there have been a large number of forms proposed for the periodic table.the version easiest to use and most closely related to the el
楼主的英文里面少内容,所以也就只能简单给你翻一下了.
自从门捷列夫和迈耶尔在19世纪七十年代第一次公布元素周期律以来,出现了很多版本和形式的元素周期表.最早使用的,同时也是与原子电子层结构最贴近的版本就是所谓的“长式周期表1”.各个元素被分入18个垂直的条栏中用以定义他们的化学族类(或组类).在每个族中,除了主电子数外,各个元素都有着相同的价电子结构.
在同一族内的元素有着非常相似的化学属性,而那些不在同一族但是价电子结数目相同元素之间也有着一定的相似性.例如,钪族元素有着相同的电子结构(n-1)d1ns2轨道,它们与拥有ns2np1轨道结构的、硼以下的元素有着一定的相似属性.因此,第三栏中钪以下的元素被称为iiib族元素,而硼所在的族被标记为iiia族元素.
元素周期表中其它的族则根据某些相似的属性进行关联和标记.3个元素栏中的viii族元素在很多属性方面都相近,从而将a副族与b副族在周期表中区分开来.