Question

Which one of the following is a correct set for \(\mathrm{SiO}_{2} ?\) (a) Angular, basic (b) Linear, basic (c) Linear, acidic (d) Tetrahedral, acidic

Short answer

Option (c) Linear, acidic is correct for \(\mathrm{SiO}_{2}\).

Step-by-step solution

Identify the Molecule

The given chemical compound is silicon dioxide, represented as \(\mathrm{SiO}_{2} \). Silicon dioxide is a well-known compound where silicon (Si) is bonded to oxygen (O) atoms.

Determine Molecular Geometry

The molecular geometry of \(\mathrm{SiO}_{2} \) needs to be identified. Silicon dioxide has a linear structure with the two oxygen atoms each double-bonded to a single silicon atom forming a \(1:2\) ratio (O=Si=O). This results in a linear geometry.

Determine Acid-Base Nature

\(\mathrm{SiO}_{2} \) is classified as an acidic oxide. When silicon dioxide is dissolved in water, it forms silicic acid, showing its acidic properties.

Match to Given Options

Among the given options, (c) Linear, acidic matches the characteristics of \(\mathrm{SiO}_{2} \), as it has a linear geometry and behaves as an acidic oxide.

Key concepts

Molecular Geometry

Molecular geometry is all about the spatial arrangement of atoms in a molecule. For silicon dioxide, \(\mathrm{SiO}_{2}\), understanding its structure is key. The molecule features silicon atom at the center with two oxygen atoms double-bonded to it. This forms a straight line, making the geometry linear.
The basic idea here is that the angles around silicon are 180 degrees because the molecule forms a "straight" configuration. This linear geometry arises because there are no lone pairs of electrons on the central silicon atom causing any deviations.

In general, molecular geometry influences many properties of a compound. For instance, the linear shape of \(\mathrm{SiO}_{2}\) contributes to its high melting point and unique hardened structure, common in sand and quartz.

Acidic Oxides

Acidic oxides are oxides that can react with water to form an acid or react with a base to form a salt and water. In the context of silicon dioxide (\(\mathrm{SiO}_{2}\)), this compound behaves as an acidic oxide.
When \(\mathrm{SiO}_{2}\) is in water, it does not dissolve easily, but when it does participate in a reaction, it can form silicic acid. This contributes to its classification as acidic.

Acidic oxides are usually formed by non-metals and are covalent in nature.

• They typically act as acidic anhydrides, which means they are expected to behave similar to an acid when hydrated or react with bases.
• This property is leveraged in various industrial and environmental applications.

Overall, understanding the acidic nature of \(\mathrm{SiO}_{2}\) can help us appreciate its reactive capabilities, especially in geochemical and biological settings.

Silicon Compounds

Silicon compounds are essential in both nature and industry. Silicon dioxide \((\mathrm{SiO}_{2})\), specifically, is one of the most common silicon compounds we encounter.
It appears in countless forms, from sand grains to crystals of quartz, and has been instrumental in technological advancements as a key component in glass production and microelectronics.

Here’s what makes silicon compounds so versatile:

• Silicon forms strong bonds with oxygen, resulting in a stable structure that is heat-resistant and robust.
• The covalent nature of its bonds leads to the formation of large, complex structures and materials.
• Silicon compounds often have low solubility in water, which is why \(\mathrm{SiO}_{2}\) maintains its hard crystalline form in nature.

By understanding silicon dioxide within the broader category of silicon compounds, we see its role in both the Earth's crust and modern technological devices.

Chemical Bonding

Chemical bonding is the force that holds atoms together within molecules. In the case of silicon dioxide \((\mathrm{SiO}_{2})\), the bonding is especially strong due to the type of bonds it forms.
Silicon atoms form double covalent bonds with oxygen atoms, a key aspect of its molecular structure.

Breaking this down further:

• Each silicon atom shares two electrons with each of the two oxygen atoms, leading to a "double bond".
• This type of bond is covalent, meaning that the electrons are shared between the atoms rather than transferred.
• Strong silicon-oxygen bonds result in a sturdy, network-like structure that accounts for the hardness and high melting point of silica species such as quartz.

Chemical bonding in \(\mathrm{SiO}_{2}\) is foundational to understanding its behavior, stability, and variety of uses in natural and manufactured environments.