Physical and Chemical Properties of Metals

Since nanoscale metal nanoparticles are applicable to a number of areas of technological importance, the nano-structured materials chemistry will occupy much attention of scientists. It is certain that controlling the primary structures of metal nanoparticles, that is, size, shape, crystal structure, composition, and phase-segregation manner is still most important, because these structures dominate the physical and chemical properties of metal nanoparticles. Now the liquid phase synthesis facilitates the precise control of the primary structures. 

In Chapter 4 we learned that the known elements can generally be divided into two classes, metals and nonmetals. On the periodic table, the elements are arranged by increasing atomic number in rows and columns. As these rows and columns are generated, the elements with metallic properties fall on the left side of the table, and the elements without metallic properties fall on the right side of the table. In Activity 6.1, we will examine the physical and chemical properties of metals to understand why they are so often the material of choice in jewelry making. 

Students will find regularities in physical and chemical properties of metals as related to each metal s position on the periodic table, and then predict which metals might be useful for jewelry making. 

Physical and Chemical Properties. The physical and chemical properties of metallic barium and its inorganic compounds have been well characterized (DOT 1986 EPA 1980a, 1984, 1985c, 1987d Hawley 1981 Hayes 1982 HSDB 1989 Kirkpatrick 1985 Kunesh 1985 Meister 1989 NIOSH/OSHA 1978 OHM/TADS 1989 Parmeggiani 1983 Perry and Chilton 1973 RTECS 1989 Sax and Lewis 1987, 1989, Sax et al. 1984 Stokinger 1981 Weast 1989 Windholz 1983). Physical and chemical properties of organic compounds of barium have not been comprehensively examined... 

Physical and Chemical Properties. The physical and chemical properties of metallic mercury and its inorganic and organic compounds have been well characterized to permit estimation of their environmental fate (Lewis 1993 Merck 1989 NFPA 1994 Osol 1980 Spencer and Voigt 1968 Verschueren 1983 Weast 1988 Weiss 1986). Most values are available for the log Kow, log Koc, Henry s law constant, vapor pressure, and solubility in water. Experimental data exist that allow characterization of the environmental fate of metallic mercury and inorganic and organic mercury compounds in a variety of environmental media. 

Compare the physical and chemical properties of metals and nonmetals. 

The metallic bond accounts for the physical and chemical properties of metals. The following structure is proposed for the metallic bond. 

PHYSICAL AND CHEMICAL PROPERTIES OF METAL CLUSTERS IN THE GAS PHASE AND ON SOLID SURFACES... 

Physical and Chemical Properties of Metal Clusters in the Gas Phase and on Solid Surfaces... 

In this chapter we discuss the physical and chemical properties of metal nanocrystals, with emphasis on size-dependent properties. The ability of nanocrystals to form mesoscopic organizations in one, two, and three dimensions is also examined. Collective properties of nanocrystal organization are presented. 

Metalloid is a term for elements that are sort-of metals, and sort-of not metals. Sometimes this group of elements is referred to as semimetals. To be more precise, these elements exhibit some of the physical and chemical properties of metals. Generally metalloids have some electrical conductivity, but not nearly as much as true metals. Because of these ambiguous definitions, even which elements are called metalloids can vary. Usually boron, silicon, germanium, arsenic, antimony, and tellurium are included as metalloids sometimes polonium and astatine rarely selenium. 

We learn that the physical and chemical properties of metals are different from those of nonmetals. These properties arise from the fundamental characteristics of atoms, particularly ionization energy. Metalloids display properties that are intermediate between those of metals and those of nonmetals. 

The more an element exhibits the physical and chemical properties of metals, the greater its metallic character. As indicated in Figure 7.12, metallic character generally increases as we proceed down a group of the periodic table and decreases as we proceed right across a period. Let s now examine the close relationships that exist between electron configurations and the properties of metals, nonmetals, and metalloids. 

Other physical and chemical properties of metallic nanoparticles are also different from the properties of the bulk materials. Gold particles less than 20 nm in diameter melt at a far lower temperature than bulk gold, for instance, and when the particles are between 2 and 3 nm in diameter, gold is no longer a noble, umeactive metal in this size range it becomes chemically reactive. 

We will examine some differences in the physical and chemical properties of metals and nonmetals. Finally, we discuss some periodic trends in the chemistry of the active metals (groups 1A and 2 A) and of several nonmetals (hydrogen and groups 6A to 8A). 

Some Physical and Chemical Properties of Metals, Nonmetals, and Metalloids... 

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