Chemical properties of zinc

The most significant chemical property of zinc is its high reduction potential. Zinc, which is above iron in the electromotive series, displaces iron ions from solution and prevents dissolution of the iron. For this reason, zinc is used extensively in coating steel, eg, by galvanizing and in zinc dust paints, and as a sacrificial anode in protecting pipelines, ship hulls, etc. 

Zinc is a bluish-white metal which dissolves readily in strong acids. In nature it occurs as a sulfide, oxide, or carbonate. In solution, it is divalent and can form hydrated Zn2+ cations in acids, and zincated anions — probably Zn(OH)42 — in strong bases (USEPA 1980, 1987). Zinc dust and powder are sold commercially under a variety of trade names Asarco, Blue powder, Cl 77949, Cl pigment metal 6, Emanay zinc dust, granular zinc, JASAD Merrillite, LI 5, and PASCO (USPHS 1989). Selected physical and chemical properties of zinc, zinc chloride, and zinc sulfate are listed in Table 9.2. 

CHEMICAL PROPERTIES OF ZINC COMPOUNDS Oxidation state + 2... 

Chemical properties of zinc, copper, vanadium, chromium, molybdenum, and cobalt... 

Physical and Chemical Properties of Zinc and Selected Compounds ... 

Important physical and chemical properties of zinc and selected zinc compounds are listed in Table 3-2. 

A FIGURE 1-3 A chemical property of zinc and gold reaction with hydrochloric acid... 

In what ways do the chemical and physical properties of zinc(ll) differ from those of iron(ll) Account for these differences. Explain what happens when... 

Properties of zinc salts of inorganic and organic salts are Hsted in Table 1 with other commercially important zinc chemicals. In the dithiocarbamates, 2-mercaptobenzothiazole, and formaldehyde sulfoxylate, zinc is covalendy bound to sulfur. In compounds such as the oxide, borate, and sihcate, the covalent bonds with oxygen are very stable. Zinc—carbon bonds occur in diorganozinc compounds, eg, diethjizinc [557-20-0]. Such compounds were much used in organic synthesis prior to the development of the more convenient Grignard route (see Grignard reactions). 

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. 

Chemistry is concerned with the properties of matter, its distinguishing characteristics. A physical property of a substance is a characteristic that we can observe or measure without changing the identity of the substance. For example, a physical property of a sample of water is its mass another is its temperature. Physical properties include characteristics such as melting point (the temperature at which a solid turns into a liquid), hardness, color, state of matter (solid, liquid, or gas), and density. A chemical property refers to the ability of a substance to change into another substance. For example, a chemical property of the gas hydrogen is that it reacts with (burns in) oxygen to produce water a chemical property of the metal zinc is that it reacts with acids to produce hydrogen gas. The rest of the book is concerned primarily with chemical properties here we shall review some important physical properties. 

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. 

One key experimental observation regarding the ZP films is that the films found on the tops of asperities are stiffer and exhibit chemical spectra indicative of longer phosphate chain lengths than films found in the valleys between asperities. These observations that differences in the conditions at the two distinct locations alter the elastic and chemical properties of the films. One of the key differences between the tops of asperities and the valleys is the pressure experienced by the zinc phosphates. Since the highest pressures, and greatest potential for wear, are achieved at the tops of the asperities, determining the response of ZPs to these pressures may aid in developing a clear picture of how the anti-wear films work. 

Jhe distribution of beryllium, boron, titanium, vanadium, chromium, cobalt, nickel, copper, zinc, gallium, germanium, tin, molybdenum, yttrium, and lanthanum in the principal coal-producing beds of the Interior Province has been studied by the U. S. Geological Survey. Data, methods of sampling, and analyses are discussed by Zubovic and others (II, 12). This chapter discusses the occurrence of 13 of these elements with respect to geological and geochemical environments of coal deposition and chemical properties of the elements. Zinc and tin are not included in this study because they were detected in only a few samples. 

H2O + 2e, 1.216 V. Electron configuration l 22y22pa3s23pic,4r2. Ionic radius Zn+2 0.75 A. Metallic radius 1.33245 A. Other physical properties of zinc are described under Chemical Elements. 

In the chemistry of the fuel cycle and reactor operations, one must deal with the chemical properties of the actinide elements, particularly uranium and plutonium and those of the fission products. In this section, we focus on the fission products and then chemistry. In Figures 16.2 and 16.3, we show the chemical composition and associated fission product activities in irradiated fuel. The fission products include the elements from zinc to dysprosium, with all periodic table groups being represented. 

Trivalent chromium compounds, except for acetate, nitrate, and chromium(III) chloride-hexahydrate salts, are generally insoluble in water. Some hexavalent compounds, such as chromium trioxide (or chromic acid) and the ammonium and alkali metal (e.g., sodium, potassium) salts of chromic acid are readily soluble in water. The alkaline metal (e.g., calcium, strontium) salts of chromic acid are less soluble in water. The zinc and lead salts of chromic acid are practically insoluble in cold water. Chromium(VI) compounds are reduced to chromium(III) in the presence of oxidizable organic matter. However, in natural waters where there is a low concentration of reducing materials, chromium(VI) compounds are more stable (EPA 1984a). For more information on the physical and chemical properties of chromium, see Chapter 3. 

In this book the chemical, structural, optical, electrical, and interface properties of zinc oxide are summarized with special emphasis on the use of ZnO as transparent conductive electrode in thin film solar cells. This application has a number of requirements, which can be fulfilled by ZnO ... 

The elements after the rare gas argon all have an inner group of electrons called the argon core and, in addition, outer electrons that determine the chemical properties of the elements. After both the 4s and 3d subsheiis are filled at zinc, the next electron goes into the 4p subshell. The elements from scandium to nickel having incomplete inner (3d) subshells comprise the first row of transition elements. The "discontinuities in the order of... 

Cadmium is a heavy metal with similar chemical properties to zinc, but is much less common in the environment than zinc. Cadmium occurs in igneous rocks and some sedimentary rocks, and is generally associated with zinc ore minerals like sphalerite, and with a range of copper ore minerals. Traces of cadmium are often present in artificial fertilizers, and this heavy metal may accumulate in soils in areas that have been used for agriculture for long periods. 

Some physical and chemical properties of ZnS and BaS04 are given in Table 2.10. Tab. 2.10 Properties of the components of zinc sulfide pigments. 

The performance properties of zinc phosphate pigments are attributed to chemical effectiveness, and the ability to form adhesion and inhibitor complexes on the surface of the substrate. In addition, in the case of zinc phosphate, electrochemical effectiveness, preferably in anodic areas, is also of note, since small amounts of the zinc phosphate will hydrolyze under moist conditions. The result of this reaction is argued to be the formation of zinc hydroxide and secondary phosphate ions, which are able to build protective layers on the metal surface in anodic areas [5.67, 5.68]. 

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