Question

What is \(\mathrm{X}\) in the following reaction? \(\mathrm{SiCl}_{4}+\mathrm{H}_{2} \mathrm{O} \rightarrow \mathrm{X}+\mathrm{HCl}\) (a) \(\mathrm{H}_{4} \mathrm{SiO}_{4}\) (b) \(\mathrm{SiH}_{4}\) (c) \((\mathrm{SiOOH})_{2}\) (d) \(\mathrm{Si}\left(\mathrm{ClO}_{4}\right)_{4}\)

Short answer

The compound \(\mathrm{X}\) is \(\mathrm{H}_4 \mathrm{SiO}_4\). (Option a)

Step-by-step solution

Identify the reactants and products

The given chemical equation is \(\mathrm{SiCl}_4 + \mathrm{H}_2 \mathrm{O} \rightarrow \mathrm{X} + \mathrm{HCl}\). \(\mathrm{SiCl}_4\) and \(\mathrm{H}_2 \mathrm{O}\) are reactants that yield \(\mathrm{X}\) and \(\mathrm{HCl}\). We need to identify what \(\mathrm{X}\) is.

Consider the reaction type

This is a hydrolysis reaction where \(\mathrm{SiCl}_4\), silicon tetrachloride, reacts with water. Typically, this results in the formation of silicic acid, as \(\mathrm{HCl}\) is produced.

Use hydrolysis knowledge to predict \(\mathrm{X}\)

Silicon tetrachloride \((\mathrm{SiCl}_4)\) typically hydrolyzes in water to form silicic acid \((\mathrm{H}_4 \mathrm{SiO}_4)\) and hydrochloric acid \((\mathrm{HCl})\). The equation can be balanced to verify, but this substance is a common product of such a reaction.

Compare with the given options

We determined that \(\mathrm{X}\) is likely \(\mathrm{H}_4 \mathrm{SiO}_4\), matching option (a). The other options \((\mathrm{SiH}_4\), \((\mathrm{SiOOH})_2\), \(\mathrm{Si} (\mathrm{ClO}_4)_4\)) don't typically result from the hydrolysis of \(\mathrm{SiCl}_4\).

Conclude identification of \(\mathrm{X}\)

Based on the typical product of \(\mathrm{SiCl}_4\) hydrolysis, option (a) \((\mathrm{H}_4 \mathrm{SiO}_4)\) is the correct identity for \(\mathrm{X}\) in the reaction given.

Key concepts

Silicon Tetrachloride

Silicon tetrachloride (\(\mathrm{SiCl}_{4}\)) is a colorless liquid at room temperature. It is commonly used in chemical reactions due to its ability to react vigorously with water. This chemical compound is a derivative of silicon, where silicon is bound to four chlorine atoms. Its high reactivity with water makes it an interesting candidate for studying hydrolysis reactions. Such reactivity is capitalized in industrial processes, especially in the manufacturing of high-purity silicon for electronics. Due to the presence of chlorine atoms, \(\mathrm{SiCl}_{4}\) should be handled carefully, as it can release hydrochloric acid (\(\mathrm{HCl}\)) upon exposure to moisture in the air. This makes understanding its chemical behavior crucial not only in laboratory experiments but also in precision-driven industrial applications.

Silicic Acid

Silicic acid (\(\mathrm{H}_{4} \mathrm{SiO}_{4}\)) is a compound that commonly results from the hydrolysis of silicon tetrachloride. It forms when water reacts with silicon compounds, breaking silicon-halogen bonds to form the more stable silicon-oxygen bonds. This transformation is a classic example of hydrolysis, where water molecules contribute to the breakdown of a substance. Silicic acid itself is not usually isolated in pure form because it tends to condense into silica or other polysilicates.
As a weak acidic compound, silicic acid contains silicon atoms bonded to hydroxyl groups, resulting in silanol groups. These silanol groups are highly reactive and often lead to the formation of silicate minerals in nature. In industrial contexts, understanding its formation and stability is crucial for the production of various silicon-based materials, used in everything from construction to electronics.

Chemical Equations

Chemical equations are symbolic representations of chemical reactions. They provide a clear and concise way to depict the reactants and products of a reaction. In the case of \(\mathrm{SiCl}_{4} + \mathrm{H}_{2}\mathrm{O} \rightarrow \mathrm{H}_{4} \mathrm{SiO}_{4} + \mathrm{HCl}\), the equation shows that silicon tetrachloride reacts with water to produce silicic acid and hydrochloric acid. It's a balanced reaction that reflects the conservation of mass, meaning the number of each type of atom on the reactant side equals that on the product side.
Writing and balancing chemical equations require a basic understanding of the stoichiometry involved. Each coefficient in a balanced equation indicates the necessary proportion between different substances. This is essential for scientists and engineers to predict how much of each substance is required or produced in a reaction. In educational contexts, practicing chemical equation balancing enhances one's ability to visualize and quantify chemical changes, fostering a deeper comprehension of chemistry's foundational principles.