Boron oxides, oxoacids and oxoanions

The principal oxide of boron, B2O3, is obtained as a vitreous solid by dehydration of boric acid at red heat (equation 

B is isoelectronic with Si P is isoelectronic with Si BP is isoelectronic with Si2 

Therefore, replacement of two Si atoms in the solid state structure of Si02 by B and P will not alfect the number of valence electrons in the system. 

Boron phosphide, BP, crystallizes with a zinc blende strnctnre. Comment on how this relates to the strnctnre of elemental silicon. 

Water is taken up slowly by B2O3 giving B(OH)3 (ortho-boric or boric acid), but above 1270 K, molten B2O3 reacts 

The commercial importance of B2O3 is in its use in the borosilicate glass industry (see Box 13.5). As a Lewis acid, B2O3 is a valuable catalyst. BPO4 (formed by reacting 

1997 for the Large Binocular Telescope, Mount Graham, Arizona. 

The structure of BPO4 is derived from that of Si02 by replacing alternate Si atoms by B or P atoms. Explain how this description relates to the isoeiectronic principle. 

B is isoeiectronic with Si P is isoeiectronic with Si BP is isoeiectronic with Si2 

Fibreglass falls into two categories textile fibres and insulation fibreglass. Of the textile fibres, alumino-borosilicate 

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