Question

Silica reacts with a hydride of superhalogen to form 'X'. On hydrolysis of 'X', another compound 'Y' is formed. 'Y' on heating at ${1000}^{\circ }C$ losses water to form 'Z'.
'Z' can also be prepared by the reaction

• A. $Si{O}_2+4HF\to Si{F}_2+2H_{2}O$
• B. $Si+O_2\to Si{O}_2$
• C. $K_{2}Si{F}_6\to 6KF+Si$
• D. $Si+2NaOH+H_2\to N{a}_{2}Si{O}_3+2H_2$

Answer 1

The correct option is B $Si+O_2\to Si{O}_2$

Silica reacts with hydride of superhalogen to form $Si{X}_4$, which is compound $X$.
$Si{O}_2+4HF\to Si{F}_4+2H_{2}O$

$Si{F}_4$ on hydrolysis gives $Si(OH{)}_4$ which is compound 'Y'.
$3Si{F}_4+4H_{2}O\to Si(OH{)}_4+2H_{2}Si{F}_6$

Compound 'Y' on heating at ${1000}^{\circ }C$ loses water to form $Si{O}_2$ which is compound 'Z'.
$Si(OH{)}_4\stackrel{\Delta }{⟶}Si{O}_2+2H_{2}O$

$Si{O}_2$ can also be prepared by the reaction of silicon with oxygen.
$Si+O_2\to Si{O}_2$