NSCI 1322 Lecture Notes - Lecture 27: Aluminium Hydroxide, Aluminium Oxide, Indium
12 Jan 2017
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Document Summary
The group 3a elements clearly show the trend of increasing metallic character in going down any column of elements in the periodic table. Boron, at the top of group 3a, is a metalloid, and its chemistry is typical of a nonmetal. The rest of the elements (aluminum, gallium, indium, and thallium) are metals, but their hydroxides change from amphoteric (acidic and basic) for aluminum and gallium to basic for indium and thallium. The group 4a elements also show the trend of greater metallic character in going down the column of elements. The last two elements of the column, tin and lead, are well- known metals, and we will discuss them in this section. Alu(cid:373)i(cid:374)u(cid:373) is the third (cid:373)ost a(cid:271)u(cid:374)da(cid:374)t ele(cid:373)e(cid:374)t i(cid:374) the earth"s (cid:272)rust (after oxygen and silicon). The weathering of these rocks results in aluminum-containing clays, which are an essential part of most soils.
