Alkali metals Group elements

Some of the alkali metal-group 15 element systems give compounds of stoichiometry ME. Of these, LiBi and NaBi have typical alloy stmc-tures and are superconductors below 2.47 K and 2.22 K respectively. Others, like LiAs, NaSb and KSb, have parallel infinite spirals of As or Sb atoms, and it is tempting to formulate them as M+ (E )" in which the (E )" spirals are iso-electronic with those of covalently catenated Se and Te (p. 752) however, their metallic lustre and electrical conductivity indicate at least some metallic bonding. Within the spiral chains As-As is 246 pm (cf. 252 pm in the element) and Sb-Sb is 285 pm (cf. 291 pm in the element). 

It is possible to explain these trends in terms of the electron configurations of the corresponding atoms. Consider first the increase in radius observed as we move down the table, let us say among the alkali metals (Group 1). All these elements have a single s electron outside a filled level or filled p sublevel. Electrons in these inner levels are much closer to the nucleus than the outer s electron and hence effectively shield it from the positive charge of the nucleus. To a first approximation, each inner electron cancels the charge of one pro-... 

The elements that form only one cation are the alkali metals (group IA), the alkaline earth metals (group IIA), zinc, cadmium, aluminum, and most often silver. The charge on the ions that these elements form in their compounds is always equal to their periodic table group number (or group number minus 10 in the newest labeling system in the periodic table). 

Group 7 A (halogens) Group 1A (alkali metals) -transition elements... 

Based upon Slater s rules, we have found that the effective nuclear charge increases sharply between periods one and three and then stays at 2.20 for the rest of the alkali metal group. You may recall that the ionization energy for an element can be calculated by using the equation ... 

Bare group 13 metal vertices (e.g., Ga, In, Tl) provide, as noted above, only one skeletal electron each to polyhedral cluster structures. Thus it is not surprising that the bare metal cluster ions Enz (E = group 13 element) found in homonuclear alkali-metal/group 13 intermetallic phases [86-89] (mainly for In and Tl) have charges less negative than the — (n + 2) (i.e., z [Pg.21]

Alkali Metal group 1 elements in the periodic table Li, Na, K, Rb, Cs, Fr Alkaline Earth Metal group 11 elements in the periodic table Be, Mg, Ca, Sr, Ba Alkaloid a nitrogen-containing compound obtained from plants, for example, caffeine, nicotine... 

A column of the periodic table is called a family. Some families have special names. Group IA elements are called alkali metals, group IIA elements are called alkaline earth metals, group VIIA elements are called halogens, and group VIIIA elements are called the noble gases. The group B elements are called transition elements. Elements with atomic numbers from 58 to 71 are called lanthanides, and elements with atomic numbers from 90 to 103 are called actinides. Families have similar chemical and physical properties. For example, the alkali metals are soft metals at room temperature they are shiny, conduct... 

Group 1 elements, beginning with lithium (Li) and running vertically to francium (Fr), are called alkali metals. Group 2 elements, beginning with beryllium (Be) and running vertically to radium (Ra), are called the alkaline earth metals. 

Alkali metals The elements found in Group 1 of the periodic table. 

The group in the Periodic Table with the least complicated chemistry is almost certainly the alkali-metal group lithium (Z — 3), sodium (Z 11), potassium (Z = 19), rubidium (Z 37), cesium (Z = 55), and the recently discovered francium (Z = 87). These elements follow directly after the inert gases and thus have one single valence electron beyond a well-shielded nucleus. 

Alkali metal An element in Group 1 (lA) of the periodic table. 

Several important groups are given names. Group IA (1) metals (not including hydrogen) are called the alkali metals. Group IIA (2) elements... 

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