Silicon and chlorine

C03-0126. A 6.82-g sample of a compound that contains silicon and chlorine is 16.53% by mass silicon. The molar mass Is less than 200 g/mol. Determine the molecular formula of the compound. 

Silicon tetrachloride (SiCy, produced when both silicon and chlorine are combined at high temperatures, is used by the military to produce smoke screens. When released in air, it reacts with the moisture in the atmosphere to produce dense clouds of water vapor. 

Table III. Transmittance of Silicon and Chlorine K x-Rays Through Air...

Write the Lewis symbols for potassium, oxygen, silicon, and chlorine. 

Dolenko GN (1993) X-ray determination of effective cheiiges on sulphur, phosphorus, silicon and chlorine atoms. J Molec Struct 291 23-57... 

The same two elements often form more than one binary compound. Their names are distinguished by the prefixes mentioned in the preceding rules. Silicon and chlorine form silicon tetrachloride, SiCl4, and disilicon hexachloride, Si2Clg. The prefix tetra-identifies four chlorine atoms in a molecule of SiC. In Si2Cl6, di- indicates two silicon atoms, and hexa- shows six chlorine atoms in the molecule. Technically, SiC should be monosilicon tetrachloride, but the prefix mono- for one is usually omitted in the first word. If an elemental name has no prefix in a binary molecular compound, you may assume that there is only one atom of that element in the molecule. 

The equation for the formation of silicon tetrachloride from silicon and chlorine is (7.8)... 

How do trends of this kind reveal themselves in the structures of the normal oxides of sodium, silicon and chlorine ... 

Barone M E and Graves D B 1995 Molecular dynamics simulations of direct reactive ion etching of silicon by fluorine and chlorine J. Appi. Phys. 78 6604-15... 

X-ray analysis of material scraped from internal surfaces indicated that it was 88% iron, 7% silicon, and 1% each of magnesium, aluminum, chlorine and sulfur. 

Look for characteristic isotopic abundances that show the presence of bromine, chlorine, sulfur, silicon, and so on. If the deduced molecular ion is of sufficient intensity, the probable molecular formula may be determined using the observed isotopic abundances of the molecular ion region. Set the deduced molecular ion, M, at 100% abundance, and then calculate the relative abundances of M + 1 and M + 2 either manually or using the data system. 

Among the Friedel-Crafts alkylations of aromatic compounds with (chlorinated alkyl)silanes, the alkylation of benzene with (tt>-chloroalkyl)silanes in the presence of aluminum chloride catalyst was generally affected by two factors the spacer length between the Cl and silicon and the electronic nature of substituents on the silicon atom of (w-chloroalkyl)silanes. As the spacer length between the C—Cl and silicon increases from (chloromethyl)silane to (/i-chloroethyl)silane to (/-chloropropyl)silane, the reactivity of the silanes increases. As the number of chloro-groups on the silicon decreases from (chloromethyl)trichlorosilanes to (chloromethyl)methyldichlorosilanes to (chloromethyl)trimethylsilanes, the... 

C03-0004. Write the chemical formula for each of the following substances (a) stearic acid, whose molecules contain 36 hydrogen atoms, 18 carbon atoms, and 2 oxygen atoms (b) silicon tetrachloride, whose molecules contain one silicon atom and four chlorine atoms and (c) Freon-113, whose molecules contain three atoms each of fluorine and chlorine and two atoms of carbon. 

C04-0145. Silicon tetrachloride is used in the electronics industry to make elemental silicon for computer chips. Silicon tetrachloride is prepared from silicon dioxide, carbon graphite, and chlorine gas. 

Many elements of the periodic table, from titanium and tin to carbon and chlorine, exhibit tetrahedral electron group geometry and tetrahedral molecular shapes. In particular, silicon displays tetrahedral shapes in virtually all of its stable compounds. 

To prepare pure silicon, silica is first converted to SiClq. A redox reaction between coke and chlorine gas is coupled with a metathesis reaction to give SiClq, which liquefies on cooling ... 

Silicon, like carbon, is relatively inactive at ordinary temperatures. But, when heated, it reacts vigorously with the halogens (fluorine, chlorine, bromine, cmd iodine) to form halides and with certain metals to form silicides. It is unaffected by all acids except hydrofluoric. At red heat, silicon is attacked by water vapor or by oxygen, forming a surface layer of silicon dioxide. When silicon and carbon are combined at electric furnace temperatures of 2,000 to 2,600 °C (3,600 to 4700 °F), they form silicon carbide (Carborundum = SiC), which is an Importeint abrasive. When reacted with hydrogen, silicon forms a series of hydrides, the silanes. Silicon also forms a series of organic silicon compounds called silicones, when reacted with various organic compounds. 

In all of the studies described above, the CuaSi samples were prepared by ion bombardment at 330 K followed by cooling of the surface to 180 K before adsorbing the methyl radicals and chlorine. AES studies as well as ion scattering results in the literature [7, 15] show that this procedure produces a surface that is enriched in silicon compared with the Cu3Si bulk stoicWometry. We have found that surfaces with less Si enrichment (possibly even copper enriched relative to the bulk stoichiometry) can be prepared by ion bombardment at temperatures below 300 K. Specifically, Cu(60 eV)/Si(92 eV) Auger peak ratios of 1.2 - 1.7 compared with a ratio of 0.5 at 400 K can be obteiined by sputtering at 180 K. 

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