107 Stories About Chemistry
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Metals are much less "diplomatic" and more consistent in their habits. Their motto is invariably "give electrons away and never accept them." They form positively charged ions. The gain of extra electrons is not in their line. Such is the rigid rule of behaviour of the metallic elements. This is the basic difference between metals and nonmetals. However, meticulous chemists have found exceptions even to this very strict rule. There are inconsistent characters even among the metals. Two (so far!), only two metals have displayed "unmetallic" features. Astatine and rhenium (the inhabitants of the 85th and 75th boxes of the Mendeleyev Table) are known to form negative univalent ions. This fact is like a black mark for the surprisingly purposeful family of metals. Now, generally speaking, which atoms part with their electrons more easily and which accept them more readily? Atoms which have few electrons on their outermost shell find it more convenient to give them away, and those which have many of them find it more profitable to complete their electron octets by acquiring them. The alkali metal shave only a single electron on their outsides. These metals think nothing of parting with it. Once they have done so they find the stable electron shell of the nearest inert gas on their outside. That is why the alkali metals are chemically the most active of all known metals. And the "very most active" among them is francium (box 87).
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