UNFILLED

These apparent anomalies are readily explained. Elements in Group V. for example, have five electrons in their outer quantum level, but with the one exception of nitrogen, they all have unfilled (I orbitals. Thus, with the exception of nitrogen. Group V elements are able to use all their five outer electrons to form five covalent bonds. Similarly elements in Group VI, with the exception of oxygen, are able to form six covalent bonds for example in SF. The outer quantum level, however, is still incomplete, a situation found for all covalent compounds formed by elements after Period 2. and all have the ability to accept electron pairs from other molecules although the stability of the compounds formed may be low. This... [Pg.40]

Silicon, germanium, tin and lead can make use of unfilled d orbitals to expand their covalency beyond four and each of these elements is able (but only with a few ligands) to increase its covalency to six. Hence silicon in oxidation state -f-4 forms the octahedral hexafluorosilicate complex ion [SiFg] (but not [SiCl] ). Tin and lead in oxidation state -1-4 form the hexahydroxo complex ions, hexahydroxostannate(IV). [Sn(OH) ] and hexahydroxoplum-bate(IV) respectively when excess alkali is added to an aqueous solution containing hydrated tin(IV) and lead(IV) ions. [Pg.163]

Once entered into a spreadsheet, data can be manipulated column at a time. For example, let us take the top cells in Table 1-3 as cells A3 and B3 (columns A and B, line 3 in Table 1-3) containing 5 and 0.305 to avoid dividing 0 by 0. Using the easycalc option of the tools menu in Excel, divide the contents of B3 by A3 and place the results in cell C3. Now select C3 and the remaining 12 unfilled cells in the column, C3 to Cl 5, and fill down using the mouse. The results of the calculation of Cp/T appear for all remaining cells in the C column. [Pg.25]

A few of the earliest methods did truncate the atom on the dividing line between regions. Leaving this unfilled valence is reasonable only for a few of the very approximate semiempirical methods that were used at that time. [Pg.202]

Modeling the lighter main group inorganic compounds is similar to modeling organic compounds. Thus, the choice of method and basis set is nearly identical. The second-row compounds (i.e., sulfur) do have unfilled d orbitals, making it often necessary to use basis sets with d functions. [Pg.285]

Free radicals like carbocations have an unfilled 2p orbital and are stabilized by substituents such as alkyl groups that release electrons Consequently the order of free radical stability parallels that of carbocations... [Pg.168]

A carbon atom with four unfilled va lences (white) appears in the Spartan-Build window as a ball and wire model... [Pg.1259]

You start building propanal using an sp C from the model kit Note that five dif ferent types of carbon are available Each is defined by a particular number of unfilled valences (these are used to make bonds) and a particular idealized geometry Valences that are not used for bonds are automatically turned into hydrogen atoms so it is nor mally unnecessary to build hydrogens into a model... [Pg.1259]

Unfilled valences 4 single 2 single 1 double 1 single 1 triple 1 single 2 partial double 3 single... [Pg.1259]

To finish building propanal you need to add two carbons and an oxygen Start by adding another sp C (it should still be selected) and continue by adding an sp C and an sp O Atoms are added by clicking on unfilled valences m the model (the valences turn into bonds)... [Pg.1259]

Examine the unfilled valences of the carboxylic acid group and find the one marked by a small circle If necessary click on the group to make this circle move to the va lence on carbon... [Pg.1261]

Click on two unfilled valences The valences are replaced by a bond... [Pg.1262]

Click on bond The bond is replaced by two unfilled valences... [Pg.1262]

Click on atom or unfilled valence Deleting an atom removes all unfilled valences associated with atom... [Pg.1262]

Unfilled Elexible Mineral-filled Granular reinforced ethylene) Perfluoroalkoxy... [Pg.1034]

Unfilled Flexible Mineral-filled Granular Glass-fiber- reinforced ... [Pg.1035]

Properties ethylene-propylene resin Poly(vinylidene fluoride) Unfilled Glass-fiber- reinforced ethylene copolymer Cellulose- filled Glass-fiber- reinforced... [Pg.1037]

Properties woodflour- and cellulose-filled Nitrile Unfilled Woodflour- filled Glass-fiber- reinforced Cellulose- filled Mineral- filled... [Pg.1039]

Properties Polyamide Poly(amide- imide), unfilled... [Pg.1042]

Nylon 6/9, molding and extrusion Nylon 6/12 Nylon 11, molding and extrusion Nylon 12, molding and extrusion Aromatic nylon (aramid), molded and unfilled ... [Pg.1042]

Properties Poly(aryl ether), unfilled Polycarbonate Thermoplastic polyester ... [Pg.1044]

Unfilled 30% glass-fiber-reinforced Unfilled 30% glass-fiber-reinforced... [Pg.1044]

Properties transparent molding low-shrink copolymer mineral-filled reinforced unfilled... [Pg.1046]

Properties Poly(methyl pentene), unfilled Polyolefin ... [Pg.1048]

Properties unfilled Fow-density Medium-density High-density weight high-density copolymer... [Pg.1049]

Properties Unfilled 20% glass-fiber- reinforced Unfilled 20% glass-fiber- reinforced Poly(ether sulfone) Poly(phenyl sulfone)... [Pg.1056]

Properties Unfilled reinforced high-impact Unfilled reinforced sulfone) sulfone)... [Pg.1057]

Properties Polyolefin Polyester isoprene butylene filled Rigid unfilled... [Pg.1059]

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