Group VIA elements oxygen

Chalcogens - The Group VIA elements (oxygen, sulfur, selenium, tellurium, and polonium). Compounds of these elements are called chalcogenides. [7]... 

EXAMPLE 4 Figure 9-3 shows a single resonance structure for ozone. Each oxygen is assigned a 6 due to the number of valence electrons present (a Group VIA element—6 electrons). 

The Group VIA elements below oxygen form some covalent compounds of the ABg type by sharing their six valence electrons with six other atoms. Sulfur hexafluoride, SFg (mp — 51 °C), an unreactive gas, is an example. Sulfur hexafluoride molecules are nonpolar octahedral molecules. The hexafluorophosphate ion, PFg, is an example of a polyatomic ion of the type AB. ... 

Each Group VIA element is less electronegative than its neighboring halogen. Oxygen and sulfur are clearly nonmetallic, but selenium is less so. Tellurium is usually classified as a metalloid and forms metal-like crystals. Its chemistry is mostly that of a nonmetal. Polonium is a metal. All 29 isotopes of polonium are radioactive. 

The Group VIA elements, except oxygen, can exhibit oxidation states ranging from —2 to +6, but not —3 or +7. Why ... 

For the following species, draw (i) diagrams that show the hybridization of atomic orbitals and (ii) three-dimensional structures that show all hybridized orbitak and outermost electrons, (iii) Determine the oxidation state of the Group VIA element (other than oxygen) in each species, (a) H2S (b) SFg (c) SF4 (d) SO2 (e) SO3. 

Ch. 6 Tellurium-Containing Heterocycles Composed of Group IVa (Carbon, Silicon, Germanium, Tin) and Group Via Elements (Tellurium, Selenium, Sulfur, Oxygen)... 

Sulfur, another Group VIA element, occurs in sulfate and sulfide minerals. Free sulfur, Sg, occurring in deep underground deposits is mined by the Frasch process. Sulfur is also produced by the Claus process, in which hydrogen sulfide (obtained from natural gas and petroleum) is partially burned. Most of the sulfur is used to prepare sulfuric acid by the contact process. In this process, sulfur is burned to sulfur dioxide, SO2, which in the presence of a catalyst and oxygen forms sulfur trioxide, SO3. This oxide dissolves in concentrated sulfuric acid, which when diluted with water gives additional sulfuric acid. Sulfuric acid is the most important compound of sulfur. 

The usual valence of indium is three, although monovalent and bivalent compounds of indium with oxygen, halogens, and Group 15 (VA) and 16 (VIA) elements ate well known. The lower valence compounds tend to disproportionate into the trivalent compound and indium metal the trivalent compounds ate stable. 

Metallurgy. The strong affinity for oxygen and sulfur makes the rare-earth metals useflil in metallurgy (qv). Mischmetal acts as a trap for these Group 16 (VIA) elements, which are usually detrimental to the properties of steel (qv) or cast iron (qv). Resistance to high temperature oxidation and thermomechanical properties of several metals and alloys are thus significantly improved by the addition of small amounts of mischmetal or its siUcide (16,17). 

Elements in the A groups have the same number of valence electrons as the Roman numeral of their group. For example, magnesium in Group llA has two valence electrons, carbon in Group IVA has four valence electrons, oxygen in Group VIA has six valence electrons, and... 

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