Group 2 elements beryllium

The Group 2 elements—beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra)—are called the alkaline earth metals. Their properties are... 

The hydrides of the later main-group elements present few problems of classification and are best discussed during the detailed treatment of the individual elements. Many of these hydrides are covalent, molecular species, though association via H bonding sometimes occurs, as already noted (p. 53). Catenation flourishes in Group 14 and the complexities of the boron hydrides merit special attention (p. 151). The hydrides of aluminium, gallium, zinc (and beryllium) tend to be more extensively associated via M-H-M bonds, but their characterization and detailed structural elucidation has proved extremely difficult. 

Boron, a metalloid with largely nonmetallic properties, has acidic oxides. Aluminum, its metallic neighbor, has amphoteric oxides (like its diagonal neighbor in Group 2, beryllium). The oxides of both elements are important in their own right, as sources of the elements, and as the starting point for the manufacture of other compounds. 

The Third-Group Elements.—The B—F bond has about 63 percent ionic character, B—O 44 percent, B—Cl 22 percent, and so forth. Bor,on forms normal covalent bonds with hydrogen. The aluminum bonds are similar to those of beryllium in ionic character. 

The product in this case is sodium aluminate, a compound that contains the aluminate ion, [Al(OH)4]. Because aluminum oxide reacts with both acids and bases, it is classified as amphoteric. Other main-group elements that form amphoteric oxides are shown in Fig. J.3. As you can see, these elements lie in a diagonal band across the table from beryllium to polonium. The acidic, amphoteric, or basic character of the oxides of the d-block metals depends on their oxidation state (see Chapter 16). 

This group contains the elements beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba) and radium (Ra). After the alkali metals, they are the second most active metals. Their electron configurations end with ns2. They become positive two charged ions by giving of their two valence electrons in chemical reactions. At room temperature, they occur in a monoatomic structure and they are solid at room temperature. Radium, a solid element, is the only radioactive member of this group. 

The organometallic compound chemistry of the 2A metals is similar to that of the 1A metals, and ionically bonded compounds predominate. As is the case with lithium in group 1 A, the first 2A element, beryllium, behaves atypically, with a greater covalent character in its metal-carbon bonds. 

In previous arrangements of the Periodic Table see Periodic Table Trends in the Properties of the Elements), the elements beryllium, magnesium, calcium, strontium, barium, and radium were referred to as members of Group Ila, or 2A. As inclusion of the word metaT in their title implies, these elements are both malleable and extrudable however, they are rather brittle. They are electrical conductors. When pure, all except the lightest, beryllium, react with atmospheric... 

Comparison of the elements of the third and fifth groups, both having three unpaired electrons leads to an explanation of their stereochemistry. Boron has one s and two p electrons and thus forms three planar sp hybrid bonds, whereas nitrogen possesses three p electrons which form bonds at right angles to each other. The comparison is similar between elements of the sixth group and beryllium, in the former case the unpaired electrons are p electrons thus forming two bonds at 90°, whilst beryllium with one s and one p electron forms two linear sp hybrid bonds. 

Barium is a member of the alkaline earth metals. The alkaline earth metals make up Group 2 (IIA) of the periodic table. The other elements in this group are beryllium, magnesium, calcium, strontium, and radium. These elements tend to be relatively active chemically and form a number of important and useful compounds. They also tend to occur abundantly in Earth s crust in a number of familiar minerals such as aragonite, calcite, chalk, limestone, marble, travertine, magnesite, and dolomite. Alkaline earth compounds are widely used as building materials. 

Magnesium is the second element in Group 2 (IIA) of the periodic table, a chart that shows how chemical elements are related to each other. The elements in Group 2 are known as the alkaline earth elements. Other elements in that group include beryllium, calcium, strontium, barium, and radium. 

Lithium, sodium, and potassium, elements of the leftmost column of the periodic table (Group lA), have a single electron in their outermost s orbital (wr ). Beryllium and magnesium, of Group HA, have two electrons in their outermost shell, ns, while boron and aluminum (Group IHA) have three electrons in their outermost shell, rn np. Similar observations can be made for other A group elements. 

The pattern metal-metalloid-nonmetal-noble gas is typical for the main group elements in each period. Period 2 begins with a metal, lithium, and ends with a noble gas, neon. In between are the metal beryllium the metalloid boron and the nonmetals carbon, nitrogen, oxygen, and fluorine. Remember that the most active metals. Groups 1 and 2, are in the s region of the periodic table. The metalloids, nonmetals, and less active metals are in the p region of the periodic table. 

The first element beryllium, as indeed is the case with all the elements of the group, has two electrons in the outermost s orbital. However, beryllium... 

---