Is silica a covalent compound?

There are misconceptions about your understanding of covalent compounds.

The oxygen atom is bonded with the silicon atom with a covalent bond. The outermost 4 electrons of silicon and carbon easily form covalent bonds.

If a covalent compound forms a molecule, such as CO2, etc., it is a covalent compound because it has a covalent bond in the molecule, but another molecular form exists, so it is a molecular crystal.

However, if a covalent compound does not exist in molecular form, such as SiO2, there is no molecule in its structure, but an atomic crystal formed by the connection of Si and O atoms.

Silica is an atomic crystal, and its chemical formula only represents the number of oxygen atoms and the number of silicon atoms is 2:1, and cannot represent a silica molecule.

Silica: covalent compound, atomic crystal.

The presence of silica.

Silica is widely found in nature and together with other minerals make up rocks. Naturally occurring silica, also known as silica, is a hard, refractory solid.

The main component of quartz is also silica, and the transparent quartz crystal is what we often call crystal.

Chemical properties of silica.

Silica is chemically inactive and does not react with water or acids (other than hydrofluoric acid), but can react with basic oxides or bases to form salts. For example:

High temperature 2NaOH+SiO2===Na2SiO3+H2O

cao+sio2===casio3

Chemical characteristics of silica: SiO2 is an acidic oxide, which is the anhydride of silicic acid. However, SiO2 has some special properties compared to other acidic oxides.

1) Most acidic oxides can be directly combined with water to form acids, but SiO2 cannot be directly combined with water. Its corresponding hydrate, silicic acid, can only be prepared by reacting with the acid with the corresponding soluble silicate (silicic acid is insoluble in water and is a weak acid, and its acidity is weaker than that of carbonic acid).

2) Acidic oxides generally do not react with acids, but SiO2 can react with hydrofluoric acid to form gaseous silicon tetrafluoride.

sio2+4hf==sif4↑+2h2o

The main component of ordinary glass and quartz glass is silica. Therefore, hydrofluoric acid can be used to corrode the glass. Hydrofluoric acid is used to carve and engrave words on glass, and hydrofluoric acid cannot be used in glass, ceramics, porcelain, and pottery containing silica in the laboratory, and plastic bottles can generally be used.

3) SiO2 reacts with a strong alkali solution to form sodium silicate, which is a mineral glue and is often used as a binder. Therefore, the reagent bottle containing alkali solution in the laboratory does not use a glass stopper, but a rubber stopper.

Silica Structure

Uses of silica.

Silica has a wide range of uses, and the main raw material of optical fibers, a high-performance communication material that has been used, is silica.

Generally, purer quartz can be used to make quartz glass. Quartz glass is commonly used in the manufacture of chemical instruments that are resistant to high temperatures.

Crystal is often used to make important components in the electronics industry, optical instruments, and is also used to make high-grade industrial products and spectacle lenses.

Silica: covalent compound, atomic crystal.

4 covalent bonds.

Because one Si in the SiO2 crystal is connected to four O atoms, there are also four Si-O bonds, and these four bonds are not related to other silicon atoms, so do not share them equally.

Reminder: Although there is no bond, the O atom plays a connecting role between 2 silicon, so when calculating the ratio of Si and O atoms, the 4 O atoms should be evenly shared, that is, 1 silicon is evenly connected with 2 O atoms, therefore, the chemical formula is SiO2

Summary. Silica is a covalent compound because the silicon and oxygen atoms are chemically bonded in the chemical structure by sharing electron pairs. A covalent bond is a sharing of electron pairs that does not involve the transfer of positive and negative charges.

In silica, the silicon atom donates 4 valence electrons and the oxygen atom donates 6 valence electrons, and by sharing these electrons, they form four covalent bonds such that each atom is able to reach a stable state of eight electrons (the state in which eight atomic orbitals are filled, known as the eight-electron rule or called inert). This way of sharing electron pairs together makes silica a covalent compound.

Silica is a covalent compound because the silicon and oxygen atoms are chemically bonded together by sharing electrons in the chemical structure. A covalent bond is a sharing of electron pairs that does not involve the transfer in the split of positive and negative charges. In silica, the silicon atom donates 4 valence electrons and the oxygen atom donates 6 valence electrons, and by sharing these electrons, they form four covalent bonds such that each atom is able to reach a stable state of eight electrons (the state in which eight atomic orbitals are filled, known as the eight-electron rule or called inert).

This way of sharing electron pairs together makes silica a covalent compound.

Can you add, I don't quite understand it.

Silica is a covalent compound, which is known for the formation of chemical bonds between silicon and oxygen atoms by sharing electrons. Covalent bonds are chemical bonds formed between atoms by sharing electrons. In silica, electrons are shared between the silicon atom and the oxygen atom, allowing each atom to reach a stable electronic profile.

The silicon atom has 4 valence electrons, while the oxygen atom has 6 valence electrons. To achieve a stable electronic configuration, each silicon atom shares an electron pair with two oxygen atoms, forming silicon-oxygen bonds. Thus, in silica, each silicon atom forms a covalent bond with two oxygen atoms, while each oxygen atom forms a covalent bond with one silicon atom.

This form of sharing electrons makes silicon-oxygen bonds very strong and stable, making silica have the characteristics of high melting point, high hardness, high heat resistance and excellent electrical insulating properties. Therefore, silica is widely used in glass, ceramics, semiconductor materials and other fields. To sum up, Void Friend silica is a covalent compound because a stable chemical bond is formed between the silicon atom and the oxygen atom by sharing electrons.

There are 4 covalent bonds in silica.

In the silica crystal, the 4 valence electrons of the silicon atom and the 4 oxygen atoms form 4 covalent bonds, the silicon atom is located in the center of the regular tetrahedron, and the 4 oxygen atoms are located on the 4 apex angles of the regular tetrahedron. Silica is an atomic crystal.

Diatomaceous earth existing in nature is amorphous silica, which is the remains of diatoms of lower aquatic plants, which is white solid or powdery, porous, light and soft solid, and has strong adsorption.

Crystalline silica is divided into three types: quartz, lemostomatite and cristobalite due to different crystal structures. Pure quartz is a colorless crystal, and the large and transparent prismatic quartz is called crystal. If the crystal containing trace impurities has different colors, there are amethyst, citrine, etc.

Ordinary sand is fine quartz crystals, with yellow sand (more iron impurities) and white sand (less impurities, purer).

Yes, there are covalent bonds present in silica (SiO2). Silica is a compound composed of silicon (Si) and oxygen (O) atoms, and its structure is formed by silicon and oxygen atoms linked together by covalent bonds. In solid-state crystals, the structure of silica forms a three-dimensional crystal structure in the form of a reticulated network, and the silicon and oxygen atoms are connected to each other by covalent bonds, forming a Si-O-Si bond.

The presence of covalent bonds gives silica high hardness, high melting point and excellent insulating properties.

Thus, the silicon and oxygen atoms in the pin silica are linked together by covalent bonds, which together form a stable compound structure.

The valency of silicon is +4. The valency of oxygen is known to be -2 valence; And because the chemical formula of silica is SiO2

Then let the valency of silicon element be x, according to the principle of valency (the algebraic sum of positive and negative valency in the compound is zero), so the pants imitation x+2 (-2)=0, the solution is x=+4, that is, silicon dioxide (SiO2

The valency of the silicon element in the medium is +4 valence.

A brief introduction to silicon

Silicon is an extremely common element, but it rarely occurs in nature in the form of a complex silicate or silica, which is widely found in rocks, gravel, and dust. Silicon is the eighth largest reserve in the universe. In the earth's crust, it is the second most abundant element, constituting the total mass of the earth's crust, after oxygen ( in the first place.

There are two allotropic forms, amorphous silicon and crystalline silicon. Crystalline silicon is gray-black, amorphous silicon is black, density grams cubic centimeters, melting point 1410, boiling point 2355, crystalline silicon belongs to atomic crystals. Insoluble in water, nitric acid and hydrochloric acid, soluble in hydrofluoric acid and lye.

Hard and metallic.

Each silicon atom in silica (referring to the chemical formula SiO2) forms a covalent bond with four oxygen atoms. This is because the silicon atom has four valence electrons and can share electrons with the four oxygen atoms to form four covalent bonds. Each oxygen atom also has two unpaired lone pairs of electrons that form a covalent bond with the two lone pairs of silicon atoms.

So, each silicon atom in silica is attached to four oxygen atoms to form a total of four covalent bonds.

It's the same substance.

Silicon dioxide. silicon dioxide

The chemical formula SiO2, also known as silica, is a hard and insoluble solid. It often occurs in three variants: quartz, lepidemite, and cristobalite quartz. Almost 65 kilometers down 16 kilometers from the ground are silica ores.

Natural silica is divided into two categories: crystalline and amorphous, and crystalline silica is mainly found in quartz ore. Pure quartz is a colorless crystal, and large, transparent prismatic quartz is a crystal. Silica is a tetrahedral structure of silicon atoms and four oxygen atoms to form an atomic crystal, the whole crystal can be regarded as a huge molecule, SiO2 is the simplest formula, does not represent a single molecule.

Density gram 3, melting point 1723 5, boiling point 2230Amorphous silica is a white solid or powder. The chemical properties are very stable.

It is insoluble in water and does not react with water quickly. It is an acidic oxide and does not react with ordinary acids. Gaseous hydrogen fluoride or hydrofluoric acid reacts with silica to form gaseous silicon tetrafluoride.

Silicates and water are formed by reacting with a hot solution of strong alkali or molten alkali. It reacts with a variety of metal oxides at high temperatures to form silicate. It is used in the manufacture of quartz glass, optical instruments, chemical utensils, ordinary glass, refractory materials, optical fibers, ceramics, etc.

The nature of silica is not active, it does not interact with halogens, hydrogen halides and hydrogen halogens other than fluorine, hydrogen fluoride and hydrofluoric acid, as well as sulfuric acid, nitric acid and perchloric acid. Hydrogen fluoride and hydrofluoric acid are the only acids that can dissolve silica, producing fluorosilicic acid, which is easily soluble in water

SiO2 6HFH2SIF6 2H2O silica can be dissolved in a strong alkaline solution with concentrated heat:

SiO2 2Naohna2SiO3 H2O At high temperatures, silica can be reduced by carbon, magnesium and aluminum:

sio2＋2csi＋2co

Two acres of rubber silica is a raw material for the manufacture of glass, quartz glass, sodium silicate, optical fibers and refractory materials.