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Periodic table alkali metals

Does the information on alkali metals in Table 12.9 of the text confirm the general periodic trends in ionization energy and atomic radius Explain. [Pg.577]

Rubidium [7440-17-7] Rb, is an alkali metal, ie, ia Group 1 (lA) of the Periodic Table. Its chemical and physical properties generally He between those of potassium (qv) and cesium (see Cesiumand cesium compounds Potassium compounds). Rubidium is the sixteenth most prevalent element ia the earth s cmst (1). Despite its abundance, it is usually widely dispersed and not found as a principal constituent ia any mineral. Rather it is usually associated with cesium. Most mbidium is obtained from lepidoHte [1317-64-2] an ore containing 2—4% mbidium oxide [18088-11-4]. LepidoHte is found ia Zimbabwe and at Bernic Lake, Canada. [Pg.278]

Sodium [7440-23-5] Na, an alkali metal, is the second element of Group 1 (lA) of the Periodic Table, atomic wt 22.9898. The chemical symbol is derived from the Latin natrium. Commercial iaterest ia the metal derives from its high chemical reactivity, low melting poiat, high boiling poiat, good thermal and electrical conductivity, and high value ia use. [Pg.161]

Among the alkali metals, Li, Na, K, Rb, and Cs and their alloys have been used as exohedral dopants for Cgo [25, 26], with one electron typically transferred per alkali metal dopant. Although the metal atom diffusion rates appear to be considerably lower, some success has also been achieved with the intercalation of alkaline earth dopants, such as Ca, Sr, and Ba [27, 28, 29], where two electrons per metal atom M are transferred to the Cgo molecules for low concentrations of metal atoms, and less than two electrons per alkaline earth ion for high metal atom concentrations. Since the alkaline earth ions are smaller than the corresponding alkali metals in the same row of the periodic table, the crystal structures formed with alkaline earth doping are often different from those for the alkali metal dopants. Except for the alkali metal and alkaline earth intercalation compounds, few intercalation compounds have been investigated for their physical properties. [Pg.38]

Perchlorates are known for most metals in the periodic table.The alkali-metal perchlorates are thermally stable to several hundred degrees above room temperature but NH4CIO4 deflagrates with a yellow flame when heated to 200° ... [Pg.868]

The person whose name is most closely associated with the periodic table is Dmitri Mendeleev (1836-1907), a Russian chemist. In writing a textbook of general chemistry, Mendeleev devoted separate chapters to families of elements with similar properties, including the alkali metals, the alkaline earth metals, and the halogens. Reflecting on the properties of these and other elements, he proposed in 1869 a primitive version of today s periodic table. Mendeleev shrewdly left empty spaces in his table for new elements yet to be discovered. Indeed, he predicted detailed properties for three such elements (scandium, gallium, and germanium). By 1886 all of these elements had been discovered and found to have properties very similar to those he had predicted. [Pg.33]

Metals and the periodic table. The periodic table groups discussed in this chapter are Groups 1 and 2, the alkali and alkaline earth metals (shaded in blue), and the transition metals (shaded in yellow). Symbols are shown for the more common metals. [Pg.535]

Alkali metal A metal in Group 1 of the periodic table, 31 hydrogen reactions with, 542 oxygen reactions with, 543-544 reactions of, 541t, 552q water reactions with, 542... [Pg.681]

Ground state The lowest allowed energy state of a species, 137 Group 1 metal. See Alkali metal Group 2 metal See Alkaline earth metal Group A vertical column of the periodic table, 31... [Pg.688]

The alkali metals are extremely reactive. Thus, there is a dramatic change in chemistry as we pass from the inert gases to the next column in the periodic table. The chemistry of the alkali metals is interesting and often spectacular. Thus, these metals react with chlorine, water, and oxygen, always forming a +1 ion that is stable in contact with most substances. The chemistry of these +1 ions, on the other hand, is drab, reflecting the stabilities of the inert gas electron arrangements that they have acquired. [Pg.96]

Another design thift Philip Stewart of the University of Oxford has revived and argued for is toe spud-form periodic system, and it hs received a good deal of recent attention. As Stewart contends, the conventional table fails to emphasize the continuity in toe sequence of the dementi Spiral systems stress continuity rather than implying breaks between the noble gright-hand edge and the alkali metals at the left edge. [Pg.128]

The element hydrogen has been placed by different authors in the alkali metals, in group 14 on top of carbon, among the halogens and sometimes simply allowed to float in an apparently unconnected manner above the main body of the periodic table. Citations for the first placement are unnecessary because this is a frequent choice. For the second, third, and fourth placements, see [36-40]. [Pg.142]

The work function of clean metal surfaces, which we denote throughout this book by O0) varies between 2 eV for alkalis up to 5.5 eV for transition metals such as Pt. In general it increases as one moves to the right on the periodic table but deviations exist (Figure 4.19 in Chapter 4). [Pg.204]

The periodic table can help us decide what type of ion an element forms and what charge to expect the ion to have. Fuller details will be given in Chapter 2, but we can begin to see the patterns. One major pattern is that metallic elements— those toward the left of the periodic table—typically form cations by electron loss. Nonmetallic elements—those toward the right of the table—typically form anions by gaining electrons. Thus, the alkali metals form cations, and the halogens form anions. [Pg.50]

As in the discussion of hydrogen, in this section we examine the properties of the alkali metals in the context of the periodic table and focus on significant applications of the elements and selected compounds. The valence electron configuration of the alkali metals is s1, where n is the period number. Their physical and chemical properties are dominated by the ease with which the single valence electron can be removed (Table 14.3). [Pg.707]

The elements show increasing metallic character down the group (Table 14.6). Carbon has definite nonmetallic properties it forms covalent compounds with nonmetals and ionic compounds with metals. The oxides of carbon and silicon are acidic. Germanium is a typical metalloid in that it exhibits metallic or nonmetallic properties according to the other element present in the compound. Tin and, even more so, lead have definite metallic properties. However, even though tin is classified as a metal, it is not far from the metalloids in the periodic table, and it does have some amphoteric properties. For example, tin reacts with both hot concentrated hydrochloric acid and hot alkali ... [Pg.724]

The alkaline earth metals, by assuming the configuration nsnp, are able to form twice as many bonds as the alkalis. Similarly the succeeding elements in the periodic table can form bonds in increasing number. [Pg.345]

The first column of the periodic table, Group 1, contains elements that are soft, shiny solids. These alkali metals include lithium, sodium, potassium, mbidium, and cesium. At the other end of the table, fluorine, chlorine, bromine, iodine, and astatine appear in the next-to-last column. These are the halogens, or Group 17 elements. These four elements exist as diatomic molecules, so their formulas have the form X2 A sample of chlorine appears in Figure EV. Each alkali metal combines with any of the halogens in a 1 1 ratio to form a white crystalline solid. The general formula of these compounds s, AX, where A represents the alkali metal and X represents the halogen A X = N a C 1, LiBr, CsBr, KI, etc.). [Pg.18]


See other pages where Periodic table alkali metals is mentioned: [Pg.264]    [Pg.300]    [Pg.25]    [Pg.12]    [Pg.13]    [Pg.13]    [Pg.21]    [Pg.425]    [Pg.175]    [Pg.31]    [Pg.170]    [Pg.22]    [Pg.178]    [Pg.889]    [Pg.1361]    [Pg.806]    [Pg.8]    [Pg.32]    [Pg.535]    [Pg.541]    [Pg.269]    [Pg.305]    [Pg.354]    [Pg.59]    [Pg.143]    [Pg.940]    [Pg.554]    [Pg.569]    [Pg.22]   
See also in sourсe #XX -- [ Pg.33 , Pg.569 ]




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