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Silicon is a chemical element; it has symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic table: carbon is above it; and germanium, tin, lead, and flerovium are below it. It is relatively unreactive.
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 ...
The first ever spectrographic analysis of a ball lightning event (in 2012) revealed the presence of silicon, iron and calcium, these elements also being present in the soil. [158] Arsenic. Metals are said to be fusible, resulting in some confusion in old chemistry as to whether arsenic was a true metal, or a nonmetal, or something in-between.
A metalloid is a chemical element which has a preponderance of properties in between, or that are a mixture of, those of metals and nonmetals. The word metalloid comes from the Latin metallum ("metal") and the Greek oeides ("resembling in form or appearance"). [1] There is no standard definition of a metalloid and no complete agreement on which ...
The dimeric silicon dioxide, (SiO 2) 2 has been obtained by reacting O 2 with matrix isolated dimeric silicon monoxide, (Si 2 O 2). In dimeric silicon dioxide there are two oxygen atoms bridging between the silicon atoms with an Si–O–Si angle of 94° and bond length of 164.6 pm and the terminal Si–O bond length is 150.2 pm.
The conductivity of silicon is increased by adding a small amount (of the order of 1 in 10 8) of pentavalent (antimony, phosphorus, or arsenic) or trivalent (boron, gallium, indium) atoms. [3] This process is known as doping, and the resulting semiconductors are known as doped or extrinsic semiconductors .
Silicon (14 Si) has 23 known isotopes, with mass numbers ranging from 22 to 44. 28 Si (the most abundant isotope, at 92.23%), 29 Si (4.67%), and 30 Si (3.1%) are stable. The longest-lived radioisotope is 32 Si, which is produced by cosmic ray spallation of argon. Its half-life has been determined to be approximately 150 years (with decay energy ...
In most silicate minerals, silicon is tetrahedral, being surrounded by four oxides. The coordination number of the oxides is variable except when it bridges two silicon centers, in which case the oxide has a coordination number of two. Some silicon centers may be replaced by atoms of other elements, still bound to the four corner oxygen corners.