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Sulfur, selenium, and tellurium

This chapter describes the chemistry of sulfur, selenium, and tellurium. Polonium will be mentioned only briefly in keeping with the fact that all of the isotopes of the element are radioactive. As a result, the chemistry of such an element is too specialized for inclusion in a survey book of this type. The plan followed in this chapter will be to discuss some of the topics of sulfur chemistry separately from those of selenium and tellurium because in several regards sulfur is somewhat different from the other two elements. [Pg.341]

As in the case of most chemical materials known in ancient times, sulfur or brimstone is sometimes found in its free state. It was one of the earliest chemicals known to humankind, and it is probable that it was recognized at least as long ago as 2000 BC. Even the ancient Romans and Egyptians knew of its medicinal use. The name sulfur is derived from the Sanscrit, sulveri, and the Latin, sulphurium. [Pg.341]

The chemistry of sulfur is a broad area that includes such chemicals as sulfuric acid (the compound prepared in the largest quantity) as well as unusual compounds containing nitrogen, phosphorus, and halogens. Although there is an extensive chemistry of selenium and tellurium, much of it follows logically from the chemistry of sulfur if allowance is made for the more metallic character of the heavier elements. All isotopes of polonium are radioactive, and compounds of the element are not items of commerce or great use. Therefore, the chemistry of sulfur will be presented in more detail. [Pg.523]

The usual form of sulfur is known as the rhombic form, which is stable at temperatures up to about 105 °C. Above that temperature, the monoclinic structure is stable. A plastic form of sulfur can be obtained by pouring liquid sulfur into water to cool it quickly, but on standing it is converted to the rhombic form. On a molecular level, the element exists as S8 rings that have the structure [Pg.524]

Sulfur vapor consists of a mixture of species that includes S8, S6, S4, and S2 (which like 02 is paramagnetic). Because the S8 molecule is nonpolar, it is soluble in liquids such as CS2 and C6H6. Selenium also consists of cyclic molecules that contain eight atoms, and tellurium is essentially metallic in character. In their vapors, several species are found that contain 2, 6, or 8 atoms. Both are useful as semiconductors, and selenium has been used in rectifiers. Because the electrical conductivity of selenium increases as the intensity of illumination increases, it has been used to operate electrical switches that open or close as a light beam is broken. Selenium was also used in light meters, but other types of meters are now available that are more sensitive. Table 15.1 gives a summary of the properties of the group VIA elements. [Pg.524]

Although many reactions and uses of sulfur will be described, about 85% of the sulfur produced is used in making sulfuric acid, and about two-thirds of the acid is used in the production of fertilizer (see Chapter 14). Sulfur is rather reactive, so it reacts with most other elements. It produces a blue flame when it bums in air, [Pg.524]

Sulfur also forms binary compounds by reacting with phosphorus and halogens. [Pg.525]


Ligands Other than Oxygen and Sulfur. See Sec. 3.1.7, Coordination Compounds, for acids containing ligands other than oxygen and sulfur (selenium and tellurium). [Pg.220]

Nitrogen and sodium do not react at any temperature under ordinary circumstances, but are reported to form the nitride or azide under the influence of an electric discharge (14,35). Sodium siHcide, NaSi, has been synthesized from the elements (36,37). When heated together, sodium and phosphoms form sodium phosphide, but in the presence of air with ignition sodium phosphate is formed. Sulfur, selenium, and tellurium form the sulfide, selenide, and teUuride, respectively. In vapor phase, sodium forms haHdes with all halogens (14). At room temperature, chlorine and bromine react rapidly with thin films of sodium (38), whereas fluorine and sodium ignite. Molten sodium ignites in chlorine and bums to sodium chloride (see Sodium COMPOUNDS, SODIUM HALIDES). [Pg.163]

Specialist Periodical Reports of the Chemical Society (London), Organic Compounds of Sulfur, Selenium and Tellurium, Vols. 1-5 (1970-79). [Pg.786]

The realization that the better ordering criterion is atomic number rather than atomic weight invites us to consider triads of atomic numbers. This reveals a most remarkable fact, namely that —50% of all conceivable triads on a conventional periodic table are in fact exact. For example, the elements sulfur, selenium, and tellurium have atomic numbers of 16, 34, and 52, respectively, thus showing that the atomic number of the middle of these three... [Pg.141]

FIGURE 1.62 The Croup 16A/I elements. From left to right oxygen, sulfur, selenium, and tellurium. Note the trend from nonmetal to metalloid. [Pg.172]

The chalcogenides are binary compounds of a chalcogen (i.e., the elements of Group Ilb zinc, cadmium, mercury) with a less electropositive element, such as those of Group VIb (oxygen, sulfur, selenium, and tellurium). This section covers the sulfides, selenides, andtellurides. Oxides are reviewed above in Ch. 11. Most of the chalcogenides have useful optical characteristics and their applications are usually found in optics. [Pg.336]

Bond Energy Terms in the Chemistry of sulfur. Selenium and Tellurium... [Pg.251]

As a matter of fact, this book is concerned with sulfur, selenium, and tellurium as components of compound or solid solution systems in which metallic or semimetal-lic elements, whatsoever, participate as well. In particular, it is focused on the electrochemistry of the inorganic compounds of sulfur, selenium, and tellurium with metals and semimetals, which collectively may be termed as metal chalcogenide (MCh) systems. [Pg.1]

Basic physical properties of sulfur, selenium, and tellurium are indicated in Table 1.3. Downward the sulfur sub-group, the metallic character increases from sulfur to polonium, so that whereas there exist various non-metallic allotropic states of elementary sulfur, only one allotropic form of selenium is (semi)metallic, and the (semi)metallic form of tellurium is the most common for this element. Polonium is a typical metal. Physically, this trend is reflected in the electrical properties of the elements oxygen and sulfur are insulators, selenium and tellurium behave as semiconductors, and polonium is a typical metallic conductor. The temperature coefficient of resistivity for S, Se, and Te is negative, which is usually considered... [Pg.7]

Table 1.3 Some physical properties of sulfur, selenium, and tellurium... Table 1.3 Some physical properties of sulfur, selenium, and tellurium...
Sheldrick WS (2007) Polychalcogenides. In DevrUanova FA (ed.), Handbook of chalcogen chemistry New perspectives in sulfur, selenium and tellurium, Royal society of Chemistry Cambridge, UK... [Pg.52]

Herteto E, Climent V, Feliu JM. 2000. On the different adsorption behavior of bismuth, sulfur, selenium and tellurium on a Pt(775) stepped surface. Electrochem Cotnmun 2 ... [Pg.242]

Metal-Sulfur, -Selenium, and -Tellurium Bond Lengths, M—E—C Angles, and Torsion Angles for Three-Coordinate Aluminum, Gallium, and Indium Thiolates, Selenolates and Tellurolates", and Related Compounds... [Pg.45]

Nitrogen, Phosphorus, Arsine, Stibine, Sulfur, Selenium, and Tellurium Ligands 153... [Pg.147]

Complexes with Sulfur-, Selenium-, and Tellurium-containing Ligands 322... [Pg.248]

SULFUR, SELENIUM, AND TELLURIUM LIGANDS 6.8.7.1 Sulfur Ligands... [Pg.1189]

See Other SULFUR, SELENIUM AND TELLURIUM TETRANITRIDES IN IMMEDIATELY... [Pg.1807]

If you move left one column in the periodic table from the halides, the chalcogenides need two electrons to complete their valence shell, and thus can bond to the surface and each other simultaneously. This appears to account for much of the interesting surface chemistry of chalcogenide atomic layers. Chalcogenides, including oxides (corrosion), are some of the most studied systems in surface chemistry. The oxides are clearly the most important, but significant amounts of work have been done with sulfur, selenium and tellurium. [Pg.64]


See other pages where Sulfur, selenium, and tellurium is mentioned: [Pg.163]    [Pg.382]    [Pg.383]    [Pg.24]    [Pg.90]    [Pg.111]    [Pg.1]    [Pg.116]    [Pg.123]    [Pg.944]    [Pg.1]    [Pg.53]    [Pg.57]    [Pg.337]    [Pg.370]    [Pg.3]    [Pg.1062]    [Pg.1147]    [Pg.122]    [Pg.163]    [Pg.166]    [Pg.191]    [Pg.129]    [Pg.283]   


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Sulfur tellurium

Sulfur, Selenium, Tellurium

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