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Silicon compounds are compounds containing the element silicon (Si). As a carbon group element, silicon often forms compounds in the +4 oxidation state, though many unusual compounds have been discovered that differ from expectations based on its valence electrons, including the silicides and some silanes. Metal silicides, silicon halides, and ...
However the chain of silicon atoms may also be branched at one or more silicon atoms. The number of possible isomers increases rapidly with the number of silicon atoms. The members of the series (in terms of number of silicon atoms) follow: silane, SiH 4, 1 silicon atom and 4 hydrogen atoms, analogous to methane
Silicides of group 1 elements are saltlike silicides, except for silane (SiH 4) whose bonds to hydrogen are covalent. Higher silane homologues are disilane and trisilane. Polysilicon hydride is a two-dimensional polymer network. Many cluster compounds of lithium silicides are known, such as Li 13 Si 4, Li 22 Si 5, Li 7 Si 3 and Li 12 Si 7. [2]
Polycarbonate is commonly used in eye protection, as well as in other projectile-resistant viewing and lighting applications that would normally indicate the use of glass, but require much higher impact-resistance. Polycarbonate lenses also protect the eye from UV light.
A silicon–oxygen bond (Si−O bond) is a chemical bond between silicon and oxygen atoms that can be found in many inorganic and organic compounds. [1] In a silicon–oxygen bond, electrons are shared unequally between the two atoms , with oxygen taking the larger share due to its greater electronegativity .
The silicon to hydrogen bond is longer than the C–H bond (148 compared to 105 pm) and weaker (299 compared to 338 kJ/mol). Hydrogen is more electronegative than silicon hence the naming convention of silyl hydrides. Commonly the presence of the hydride is not mentioned in the name of the compound. Triethylsilane has the formula Et 3 SiH.
Silicon can form sigma bonds to other silicon atoms (and disilane is the parent of this class of compounds). However, it is difficult to prepare and isolate Si n H 2n+2 (analogous to the saturated alkane hydrocarbons ) with n greater than about 8, as their thermal stability decreases with increases in the number of silicon atoms.
A fifth allotrope of carbon, discovered in 2003, is called graphene, and is in the form of a layer of carbon atoms arranged in a honeycomb-shaped formation. [6] [14] [15] Silicon has two known allotropes that exist at room temperature. These allotropes are known as the amorphous and the crystalline allotropes. The amorphous allotrope is a brown ...