Search results
Results From The WOW.Com Content Network
Silicon dioxide is a relatively inert material (hence its widespread occurrence as a mineral). Silica is often used as inert containers for chemical reactions. At high temperatures, it is converted to silicon by reduction with carbon. Fluorine reacts with silicon dioxide to form SiF 4 and O 2 whereas the other halogen gases (Cl 2, Br 2, I 2 ...
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide).The atoms are linked in a continuous framework of SiO 4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO 2.
The magnesium silicide reacts with the acid to produce silane gas, which burns on contact with air and produces tiny explosions. [11] This may be classified as a heterogeneous [ clarification needed ] acid–base chemical reaction, since the isolated Si 4− ion in the Mg 2 Si antifluorite structure can serve as a Brønsted–Lowry base capable ...
Carbothermal reduction of silicon dioxide in a nitrogen atmosphere at 1400–1450 °C has also been examined: [9] 3 SiO 2 + 6 C + 2 N 2 → Si 3 N 4 + 6 CO. The nitridation of silicon powder was developed in the 1950s, following the "rediscovery" of silicon nitride and was the first large-scale method for powder production.
Fused silica can be made from almost any silicon-rich chemical precursor, usually using a continuous process which involves flame oxidation of volatile silicon compounds to silicon dioxide, and thermal fusion of the resulting dust (although alternative processes are used). This results in a transparent glass with an ultra-high purity and ...
Silica gel is an amorphous and porous form of silicon dioxide (silica), consisting of an irregular tridimensional framework of alternating silicon and oxygen atoms with nanometer-scale voids and pores. The voids may contain water or some other liquids, or may be filled by gas or vacuum. In the last case, the material is properly called silica ...
The properties of silicon may be used to modify alloys with metals other than iron. "Metallurgical grade" silicon is silicon of 95–99% purity. About 55% of the world consumption of metallurgical purity silicon goes for production of aluminium-silicon alloys ( silumin alloys) for aluminium part casts , mainly for use in the automotive industry .
The Si-O-M linkage between the silicates and the metals are strong, polar-covalent bonds. Silicate anions ([SiO 2+n] 2n−) are invariably colorless, or when crushed to a fine powder, white. The colors of silicate minerals arise from the metal component, commonly iron. In most silicate minerals, silicon is tetrahedral, being surrounded by four ...