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Copper chemical properties

Is 2s 2p 3s 3p 3d 4s. If the 3d states were truly core states, then one might expect copper to resemble potassium as its atomic configuration is ls 2s 2p 3s 3p 4s The strong differences between copper and potassium in temis of their chemical properties suggest that the 3d states interact strongly with the valence electrons. This is reflected in the energy band structure of copper (figure Al.3.27). [Pg.129]

Among the metals, for example, sodium and potassium are similar to each other and form similar compounds. Copper and iron are also metals having similar chemical properties but these metals are clearly different from sodium and potassium—the latter being soft metals forming mainly colourless compounds, whilst copper and iron are hard metals and form mainly coloured compounds. [Pg.1]

The chemical properties of phthalocyanines depend mosdy on the nature of the central atom. Phthalocyanines are stable to atmospheric oxygen up to approximately 100°C. Mild oxidation may lead to the formation of oxidation iatermediates that can be reduced to the original products (29). In aqueous solutions of strong oxidants, the phthalocyanine ring is completely destroyed and oxidized to phthalimide. Oxidation ia the presence of ceric sulfate can be used to determine the amount of copper phthalocyanine quantitatively (30). [Pg.504]

The unique nature of the electronic configuration of copper, which contributes to its high electrical and heat conductivity, also provides chemical properties intermediate between transition and 18-sheU elements. Copper can give up the 4s electron to form the copper(I) ion [17493-86-6] or release an additional electron from the >d orbitals to form the copper(Il) ion [15158-11-9]. [Pg.195]

Various materials are used in dental prosthetic practice for the preparation of dental implants, crowns, and bridges. Some of these materials contain copper, which is added in order to improve mechanical or/and chemical properties, but some of them may contain the copper as an impurity. Considering the fact that dental implants remain in the oral cavity for a long time, and that they are exposed to the corrosive action of oral fluids and various kinds of food and beverages, it is necessary to check their possible harmful effects upon the human health. [Pg.373]

The Group 1 elements are soft, low-melting metals which crystallize with bee lattices. All are silvery-white except caesium which is golden yellow "- in fact, caesium is one of only three metallic elements which are intensely coloured, the other two being copper and gold (see also pp. 112, 1177, 1232). Lithium is harder than sodium but softer than lead. Atomic properties are summarized in Table 4.1 and general physical properties are in Table 4.2. Further physical properties of the alkali metals, together with a review of the chemical properties and industrial applications of the metals in the molten state are in ref. 11. [Pg.74]

Whereas the utility of these methods has been amply documented, they are limited in the structures they can provide because of their dependence on the diazoacetate functionality and its unique chemical properties. Transfer of a simple, unsubstituted methylene would allow access to a more general subset of chiral cyclopropanes. However, attempts to utilize simple diazo compounds, such as diazomethane, have never approached the high selectivities observed with the related diazoacetates (Scheme 3.2) [4]. Traditional strategies involving rhodium [3a,c], copper [ 3b, 5] and palladium have yet to provide a solution to this synthetic problem. The most promising results to date involve the use of zinc carbenoids albeit with selectivities less than those obtained using the diazoacetates. [Pg.86]

This example of aluminium illustrates the importance of the protective him, and hlms that are hard, dense and adherent will provide better protection than those that are loosely adherent or that are brittle and therefore crack and spall when the metal is subjected to stress. The ability of the metal to reform a protective him is highly important and metals like titanium and tantalum that are readily passivated are more resistant to erosion-corrosion than copper, brass, lead and some of the stainless steels. There is some evidence that the hardness of a metal is a signihcant factor in resistance to erosion-corrosion, but since alloying to increase hardness will also affect the chemical properties of the alloy it is difficult to separate these two factors. Thus althou copper is highly susceptible to impingement attack its resistance increases with increase in zinc content, with a corresponding increase in hardness. However, the increase in resistance to attack is due to the formation of a more protective him rather than to an increase in hardness. [Pg.192]

Acknowledgement This section is based on the article Chemical Properties and Corrosion Resistance of Copper and Copper Alloys which formed Chapter XVIII of the American Chemical Society Monograph No. 122, Copper The Science and Technology of the Metal its Alloys and Compounds, edited by Professor Allison Butts, and published by the Reinhold Publishing Corporation, New York, in 1954. Acknowledgement is hereby made to the Reinhold Publishing Corporation for permission to use the above-mentioned section as a basis for the present chapter. [Pg.709]

A.4 Identify all the chemical properties and changes in the following statement Copper is a red-brown element obtained from copper sulfide ores by heating them in air, which forms copper oxide. Heating the copper oxide with carbon produces impure copper, which is purified by electrolysis. ... [Pg.38]

The existence of copper(I) isocyanide complexes is well documented, of course (90). Such complexes are basically straightforward, having stoichiometries and physical and chemical properties analogous to other copper(I) complexes. It would be somewhat surprising if the studies currently underway on the catalytic systems had not attempted to sketch in this relationship more precisely. No copper(O) isocyanide complexes are known, so such species if they exist here would be particularly interesting their stability is clearly low with respect to ligand dissociation, or they would have been isolated in these studies. [Pg.49]

The most important information about the nanoparticles is the size, shape, and their distributions which crucially influence physical and chemical properties of nanoparticles. TEM is a powerful tool for the characterization of nanoparticles. TEM specimen is easily prepared by placing a drop of the solution of nanoparticles onto a carbon-coated copper microgrid, followed by natural evaporation of the solvent. Even with low magnification TEM one can distinguish the difference in contrast derived from the atomic weight and the lattice direction. Furthermore, selective area electron diffraction can provide information on the crystal structure of nanoparticles. [Pg.58]

The chemical properties of copper, lead, lead-zinc, and zinc slags are essentially as ferrous silicates, whereas nickel slags are primarily calcium/magnesium silicates. Table 4.13 lists typical chemical compositions of these slags. [Pg.171]

Chaignon, V., SanchezNeira, I., Herrmann, P., Jadlard, B. and Hinsinger, P. (2003). Copper bioavailability and extractability as related to chemical properties of contaminated soils from a vine-growing area , Environmental Pollution, 123, 229-238. [Pg.409]

Although zinc is formally a 4-block element, some of its chemical properties are similar to those of the alkaline earth metals, especially those of magnesium. This is mainly due to zinc s exclusive exhibition of the +2 oxidation state in all its compounds and its appreciable electropositive character. With a standard potential of —0.763 V, zinc is considerably more electropositive than copper and cadmium. [Pg.314]

Pathan, H. M. Desai, J. D. Lokhande, C. D. 2002. Modified chemical deposition and physico-chemical properties of copper sulphide (Cu2S) thin films. Appl. Surf. Sci. 202 47-56. [Pg.277]

The higher coordinating ability and Lewis acidity of Zn(H) ion in addition to the low pK of the metal-bound water molecule and the appearance of this metal ion in native phosphatases inspired a number of research groups to develop Zn(II)-containing dinuclear artificial phosphatases. In contrast, very few model compounds have been published to mimic the activity of Fe(III) ion in dinuclear centers of phosphatase enzymes. Cu(II) or lanthanide ions are not relevant to natural systems but their chemical properties in certain cases allow extraordinarily high acceleration of phosphate-ester hydrolysis [as much as 108 for copper(II) or 1013 for lanthanide(III) ions]. [Pg.223]


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See also in sourсe #XX -- [ Pg.409 ]

See also in sourсe #XX -- [ Pg.409 ]

See also in sourсe #XX -- [ Pg.252 ]

See also in sourсe #XX -- [ Pg.966 ]




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Copper properties

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