Question

The coordination numbers of oxygen and silicon in ${{Si}}{{{O}}_{{2}}}$ respectively?
A. $1,2$
B. $2,1$
C. $2,4$
D. $4,2$

Answer 1

The coordination number of an atom for molecules and polyatomic ions is found by counting the other atoms to which it is bonded, it can be single multiple bonds. Here, silicon is bound to two atoms and oxygen to one atom.

Complete step by step answer:
${{Si}}{{{O}}_{{2}}}$ is an oxide of silicon. Its chemical name is silicon dioxide. It is also named as silica, kalii bromidum, silicic oxide or silicic acid. It widely occurs in nature as quartz.
It is obtained in the form of transparent to grey form in the crystalline or amorphous powdered form. It is an odourless and tasteless compound. It is a compound of wide applications. It is used in the production of concrete in construction etc. Silicon Dioxide is produced by the acidification of sodium silicate solutions. Silica gel is then washed and dehydrated to give colourless microporous silica.
In ${{Si}}{{{O}}_{{2}}}$ one silicon is doubly bonded with two oxygen atoms. Therefore, the coordination number of silicon is two. The two oxygen atoms are bonded to silicon only therefore, the coordination number is one.

So, the correct answer is Option B.

Additional Information:
Silica taken orally is non-toxic with higher levels dementia is decreased. But when fine silica particles are inhaled in high quantities, it increases the risk of rheumatoid arthritis.

Note: Silicates are the minerals containing silicon and oxygen. The basic structural unit of a silicate mineral is the ${{SiO}}_{{4}}^{{{4 - }}}$ tetrahedron. In a ${{SiO}}_{{4}}^{{{4 - }}}$ tetrahedron each Silicon atom is covalently bonded to $4$ oxygen atoms. Zeolites are aluminosilicate mainly used as adsorbents and catalysts. It has a porous structure and can accommodate a lot of cations, such as ${{N}}{{{a}}^{{ + }}}{{, }}{{{K}}^{{ + }}}{{, C}}{{{a}}^{{{2 + }}}}{{, M}}{{{g}}^{{{2 + }}}}$and others. These positive ions are loosely held and can readily exchange.