Question

${\text{SiC}}{{\text{l}}_{\text{4}}}$ on hydrolysis gives:
(A) Silica
(B) Silicic acid
(C) Silicone
(D) Silicate

Answer 1

The reaction of any substance with water leading to the breakdown of the substance is known as hydrolysis. During hydrolysis, the bonds break and energy is released.

Step by step answer: The reaction of any substance with water leading to the breakdown of the substance is known as hydrolysis.
The reaction of silicon tetrachloride $\left( {{\text{SiC}}{{\text{l}}_{\text{4}}}} \right)$ with water i.e. hydrolysis of silicon tetrachloride is,
${\text{SiC}}{{\text{l}}_{\text{4}}}{\text{ + 4}}{{\text{H}}_2}{\text{O }} \to {\text{ Si}}{\left( {{\text{OH}}} \right)_{\text{4}}}{\text{ + 4HCl}}$
In the reaction, ${\text{Si}}{\left( {{\text{OH}}} \right)_{\text{4}}}$ and ${\text{HCl}}$ are produced.
Silica is ${\text{Si}}{{\text{O}}_{\text{2}}}$. Thus, option (A) is not correct.
Silicic acid is ${\text{Si}}{\left( {{\text{OH}}} \right)_{\text{4}}}$. Thus, option (B) is correct.
Silicone is $- {{\text{R}}_2}{\text{Si}} - {\text{O}} - {\text{Si}}{{\text{R}}_2} -$. Thus, option (C) is not correct.
Silicate is ${\left( {{\text{S}}{{\text{i}}_2}{\text{O}}_5^{2 - }} \right)_n}$. Thus, option (D) is not correct.
Thus, ${\text{SiC}}{{\text{l}}_{\text{4}}}$ on hydrolysis gives silicic acid.

Thus, the correct option is (B) silicic acid.

Additional Information: Properties of silicon tetrachloride are as follows:
-Silicon tetrachloride is a colourless liquid. It has pungent odor and fuming nature.
-Silicon tetrachloride can be decomposed to hydrochloric acid by water. Heat is evolved during this reaction.
-Silicon tetrachloride corrodes metals in presence of moisture.
-Silicon tetrachloride is soluble in benzene, toluene, chloroform, ether, etc. It is not soluble in water instead it reacts with water.

Note: Silicic acid is also known as orthosilicic acid. Many silicates can be derived from silicic acid. Do not get confused between hydrolysis and hydration.
During hydrolysis, salt and water react to produce acidic or basic solutions. An example of hydrolysis is-
${\text{SiC}}{{\text{l}}_{\text{4}}}{\text{ + 4}}{{\text{H}}_2}{\text{O }} \to {\text{ Si}}{\left( {{\text{OH}}} \right)_{\text{4}}}{\text{ + 4HCl}}$