Beryllium, for example, is classified as an alkaline earth metal although its amphoteric chemistry and tendency to mostly form covalent compounds are both attributes of a chemically weak or post transition metal.
42.
Since the alumina is amphoteric, it dissolves in the sodium hydroxide, leaving impurities less soluble at high pH such as iron oxides behind in the form of a highly alkaline red mud.
43.
It has an unusual crystalline structure featuring mixed metallic-covalent bonding and low symmetry It bonds covalently in most of its compounds, has an amphoteric oxide; and can form anionic gallates.
44.
They react with amphoteric oxides : for example, the oxides of aluminium, zinc, tin, and lead react with the alkali metal hydroxides to give aluminates, zincates, stannates, and plumbates.
45.
The oxides of indium in its preferred oxidation state of + 3, namely In 2 O 3 and In ( OH ) 3 are weakly amphoteric; it forms anionic indates in strongly basic solutions.
46.
Chromium ( III ) hydroxide ( Cr ( OH ) 3 ) is amphoteric, dissolving in acidic solutions to form [ Cr ( H 2 O ) 6 ] 3 +, and in basic solutions to form.
47.
Some other elements which form amphoteric oxides are gallium, indium, scandium, titanium, zirconium, vanadium, chromium, iron, cobalt, copper, silver, gold, germanium, tin, antimony, bismuth, and tellurium
48.
The oxide ( CuO ) is amphoteric, with predominating basic properties; it can be fused with alkali oxides ( M 2 O; M = Na, K ) to give anionic oxycuprates ( M 2 CuO 2 ).
49.
Steele notes the paradoxical chemical behaviour of aluminium : " It resembles a weak metal in its amphoteric oxide and in the covalent character of many of its compounds . . . Yet it is a highly high negative electrode potential ".
50.
The hydroxyl groups coating an oxide surface such as that of SiO 2 can donate or accept a proton and thus behave in an amphoteric way as illustrated by the following acid-base reactions occurring at the oxide-electrolyte interface:
