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What is silicon dioxide

The chemical formula of silicon dioxide is SiO2. Silicon dioxide has two forms: crystalline and amorphous. Silica existing in nature, such as quartz, and quartz sand, is collectively called silica. Pure quartz is a colorless crystal. Large and transparent prismatic quartz crystals are called crystals. Those with trace impurities and purple are called amethyst. Those with light yellow, golden yellow, and brown are called smoky crystals. Chalcedony, agate, and jasper are colored quartz crystals containing impurities. Sand is a fine particle of quartz mixed with impurities. Opal and diatomite are amorphous silica. Silica is widely used, mainly for making glass, water glass, pottery, enamel, refractory, aerogel felt, ferrosilicon, molding sand, simple silicon, cement, etc. In ancient times, silica was used to make glaze and porcelain matrices. General stones are mainly composed of silica and calcium carbonate. The chemical properties are relatively stable. Does not react with water. It has high fire resistance, high-temperature resistance, low coefficient of thermal expansion, increased insulation, corrosion resistance, piezoelectric effect, resonance effect, and unique optical characteristics. [11] It is an acidic oxide and does not react with general acids. Hydrofluoric acid reacts with silicon dioxide to produce gaseous silicon tetrafluoride. React with a hot concentrated alkali solution or molten alkali to make silicates and water. React with various metal oxides at high temperatures to form silicates. The nature of silica is not active and does not react with halogens, hydrogen halides, sulfuric acid, nitric acid, and perchloric acid (excluding hot concentrated phosphoric acid) except for fluorine and hydrogen fluoride. The common concentrated phosphoric acid (or pyrophosphoric acid) can corrode silicon dioxide at high temperatures, generating hetero-poly acids. At high temperatures, molten borate or boron anhydride can corrode silicon dioxide. Given this property, borate can be used as a flux in ceramic firing. In addition, hydrogen fluoride can also dissolve silicon dioxide into acids, generating water-soluble fluorosilicic acid. Silicon and carbon have similar properties, but there are significant differences in the properties of their oxides. CO2 is a molecular crystal, while SiO2 is an atomic crystal. SiO2 is a three-dimensional network structure formed with the silicon-oxygen tetrahedron as the basic structure. In the crystal structure, four valence electrons of silicon atoms form four covalent bonds with four oxygen atoms. The silicon atom is in the center of the regular tetrahedron, and the O atom is at the apex of the tetrahedron. If you are looking for high quality, high purity and cost-effective silicon dioxide, or if you require the latest price of silicon dioxide, please feel free to email contact mis-asia.

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