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High electrical conductivity

He observed an f-factor of 3 and argued for the formation of the di-protonated acid. He interpreted the high electrical conductivity of these media in support of this. [Pg.14]

Solutions of nitric acid in 100% sulphuric acid have a high electrical conductivity. If nitric acid is converted into a cation in these solutions, then the migration of nitric acid to the cathode should be observed in electrolysis. This has been demonstrated to occur in oleum and, less conclusively, in concentrated acid, observations consistent with the formation of the nitronium ion, or the mono- or di-protonated forms of nitric acid. Conductimetric measurements confirm the quantitative conversion of nitric acid into nitronium ion in sulphuric acid. ... [Pg.14]

The salts had a high electrical conductivity, and it was claimed that the values of the molar conductances at infinite dilution showed the formation of a binary and ternary electrolyte respectively. [Pg.14]

The metallic salts of trifluoromethanesulfonic acid can be prepared by reaction of the acid with the corresponding hydroxide or carbonate or by reaction of sulfonyl fluoride with the corresponding hydroxide. The salts are hydroscopic but can be dehydrated at 100°C under vacuum. The sodium salt has a melting point of 248°C and decomposes at 425°C. The lithium salt of trifluoromethanesulfonic acid [33454-82-9] CF SO Li, commonly called lithium triflate, is used as a battery electrolyte in primary lithium batteries because solutions of it exhibit high electrical conductivity, and because of the compound s low toxicity and excellent chemical stabiUty. It melts at 423°C and decomposes at 430°C. It is quite soluble in polar organic solvents and water. Table 2 shows the electrical conductivities of lithium triflate in comparison with other lithium electrolytes which are much more toxic (24). [Pg.315]

The successfiil synthesis of a transparent soHd polymer electrolyte (SPE) based on PEO and alkoxysilanes has been reported (41). The material possessed good mechanical properties and high electrical conductivity (around 1.8 x 10 S/cm at 25°C) dependent on the organic—inorganic ratio and PEO chain length. [Pg.329]

Copper is by far the most widely used conductor material. It has high electrical conductivity, thermal conductivity, solderabiUty, and resistance to corrosion, wear, and fatigue. Annealed copper conductors can withstand flex and vibration stresses normally encountered in use. [Pg.534]

Carbon Blacks. The high electrical conductivity of carbon black is utili2ed where its color is not objectionable and its reinforcing action is used (see Fillers Composites). Carbon black increases the electrical conductance of the polymer to which it is added, and therefore its effectiveness does not depend on moisture absorption (see Carbon, carbon black). [Pg.296]

Borides have metallic characteristics such as high electrical conductivity and positive coefficients of electrical resistivity. Many of them, particularly the borides of metals of Groups 4 (IVB), 5 (VB), and 6 (VIB), the MB compounds of Groups 2(11) and 13(111), and the borides of aluminum and siUcon, have high melting points, great hardness, low coefficients of thermal expansion, and good chemical stabiUty. [Pg.218]

Graphite properties conducive to successful electrolytic appHcation include high electrical conductivity, high degree of insolubiUty and operation at low voltage, high purity, low initial cost, easily machinable, and few limitations as to size and shape. [Pg.521]

Copper has a high electrical conductivity that is second only to that of silver. The conductivity of silver in % lACS units is 108 gold, 73 aluminum, 64 and iron, 18. Wrought copper having a conductivity near 102% lACS is not uncommon because of improvements in refining practices since the standard was first estabUshed. [Pg.222]

Contamination of the melt with elements that remain in soHd solution must be avoided, and excess deoxidi2er must be controEed to obtain castings of high electrical conductivity. Properties are shown in Table 8. [Pg.248]

Aluminum and Alloys Aluminum and its alloys are made in practically all the forms in which metals are produced, including castings. Thermal conductivity of aluminum is 60 percent of that of pure copper, and unalloyed aluminum is used in many heat-transfer applications. Its high electrical conductivity makes aluminum popular in electrical apphcations. Aluminum is one of the most workable of metals, and it is usually joined by inert-gas-shielded arc-welding techniques. [Pg.2450]

The easy movement of the electrons gives the high electrical conductivity of metals. The metallic bond has no directionality, so that metal ions tend to pack to give simple, high-density structures, like ball-bearings shaken down in a box. [Pg.40]

These equilibria effect a rapid exchange of N atoms between the various species and only a single N nmr signal is seen at the weighted average position of HNO3, [NOa]" " and [N03]. They also account for the high electrical conductivity of the pure (stoichiometric) liquid (Table 11.13), and are an important factor in the chemical reactions of nitric acid and its non-aqueous solutions see below. [Pg.467]

H2SO4.Z2H2O, are known with = 1, 2, 3, 4 (mps 8.5", -39.5". -36.4" and -28.3% respectively). Other compounds in the H2O/SO3 system are H2S2O7 (mp 36") and H2S4O13 (mp 4"). Anhydrous H2SO4 is a remarkable compound with an unusually high dielectric constant, and a very high electrical conductivity which results from the ionic self-dissociation (autoprotolysis) of the compound coupled with a proton-switch mechanism for the rapid... [Pg.710]

High-temperature reduction of Na2Ti03 with hydrogen produces nonstoichiometric materials, Na jTi02 (jr = 0.20-0.25), called titanium bronzes by analogy with the better-known tungsten bronzes (p. 1016). They have a blue-black, metallic appearance with high electrical conductivity and are chemically inert (even hydrofluoric acid does not attack them). [Pg.964]

To use lower gas temperatures (under 1,500 K), noble gases like argon and helium offer vei y high electrical conductivities. Recycling the noble gas leads to the closed cycle MHD process. [Pg.745]

Silver is often preferred as an undercoat for rhodium by reason of its high electrical conductivity. A further advantage of silver in the case of the thicker rhodium deposits (0-0025 mm) applied to electrical contacts for wear resistance is that the use of a relatively soft undercoat permits some stress relief of the rhodium deposit by plastic deformation of the under-layer, and hence reduces the tendency to cracking , with a corresponding improvement in protective value. Nickel, on the other hand, may be employed to provide a measure of mechanical support, and hence enhanced wear resistance, for a thin rhodium deposit. A nickel undercoating is so used on copper printed connectors, where the thickness of rhodium that may be applied from conventional electrolytes is limited by the tendency of the plating solution to attack the copper/laminate adhesive, and by the lifting effect of internal stress in the rhodium deposit. [Pg.561]

The diagonal line or stairway that starts to the left of boron in the periodic table (Figure 2.7, page 31) separates metals from nonmetals. The more than 80 elements to the left and below that line, shown in blue in the table, have the properties of metals in particular, they have high electrical conductivities. Elements above and to the right of the stairway are nonmetals (yellow) about 18 elements fit in that category. [Pg.33]

The high electrical conductivity of metals as well as the high electron (and hole) mobility of inorganic covalently bound semiconductors have both been clarified by the band theory [I9, which slates that the discrele energy levels of individual atoms widen in the solid stale into alternatively allowed and forbidden bands. The... [Pg.565]

The high electrical conductivity of a substance like copper or silver is familiar to all. Conduc-... [Pg.80]

In Chapter 5 we identified metals by their high electrical conductivity. Now we can explain why they conduct electric current so well. It is because there are some electrons present in the crystal lattice that are extremely mobile. These conduction electrons move throughout the metallic crystal without specific attachment to particular atoms. The alkali elements form metals because of the ease of freeing one electron per atom to provide a reservoir of conduction electrons. The ease of freeing these conduction electrons derives from the stability of the residual, inert gas-like atoms. [Pg.94]

A second characteristic property of metals is high electrical conductivity. The conductivity is so much higher than that of aqueous electrolyte solutions that the charge movement cannot involve the same mechanism. Again we find a... [Pg.303]

In diamond, carbon is sp hybridized and forms a tetrahedral, three-dimensional network structure, which is extremely rigid. Graphite carbon is sp2 hybridized and planar. Its application as a lubricant results from the fact that the two-dimensional sheets can slide across one another, thereby reducing friction. In graphite, the unhybridized p-electrons are free to move from one carbon atom to another, which results in its high electrical conductivity. In diamond, all electrons are localized in sp3 hybridized C—C cr-bonds, so diamond is a poor conductor of electricity. [Pg.1011]


See other pages where High electrical conductivity is mentioned: [Pg.1960]    [Pg.357]    [Pg.285]    [Pg.119]    [Pg.417]    [Pg.190]    [Pg.26]    [Pg.92]    [Pg.291]    [Pg.359]    [Pg.248]    [Pg.39]    [Pg.42]    [Pg.40]    [Pg.216]    [Pg.3]    [Pg.175]    [Pg.249]    [Pg.987]    [Pg.1272]    [Pg.612]    [Pg.770]    [Pg.244]    [Pg.691]    [Pg.81]    [Pg.232]    [Pg.45]   
See also in sourсe #XX -- [ Pg.257 ]




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