Group IIB Zn, Cd, Hg

Group-IB (Cu, Ag, Au) or -IIB (Zn, Cd, Hg)-Transition-Metal Bonds 8.3.3. Group IIB-Transition- and Inner-Transition-Metal Bonds 8.3.3.4. by Insertion into a Bond Insertion of a Group-IIB Element... 

All three metals (Zn, Cd, Hg) in Group 12 (IIB) have a ground state electron configuration ending with... 

Class 2, with the metals, is roughly speaking, further divided, into main group elements (class 2.2) and transition metals (2.1). Aluminum is missing, from class 2.2, but is quite near the border of the class. This set is also in the other classification of elements of group 12 (IIB) (Zn, Cd, and Hg), which is reasonable from the point of view of electron configuration, as well as elements of group 3 (IIIB) (Sc, Y, La), the lanthanides, and thorium. 

Group IIB ineludes Zn, Cd and Hg. Zine has some resemblanee to magnesium but the other metals in the group have little in eommon. At room temperature mereury is unaffeeted by air, water or non-oxidizing agents whereas zine is more reaetive, albeit tempered by a proteetive hydroxide film, a property utilized in galvanizing. 

The synthesis of compounds containing boron-group IIB bonds also occurs by two pathways. The most convenient method is using anionic borane or carboranc species, as in the group-IB case, to react with Zn, Cd, or Hg halides. Moreover, reactions between organometallic compounds (Zn, Cd) with unchanged boranes arc also realized, so Zn and Cd decaboranes, e.g., MB H 2 n solvent (M = Zn, Cd), result from reactions of decaborane(14) with MRj . 

Figure 2.1 shows that the main driving force for these reactions is, in general, the strongly exothermic formation of the metal halide. This is particularly striking for the Group IIB elements, Zn, Cd and Hg, where the methyls are in each case... 

Zinc (Zn) is a bluish-white, lustrous metal and was discovered in 1746. It is extensively used to form numerous alloys with other metals. Cadmium (Cd) was discovered in 1817 from an impurity in zinc carbonate. Cd is a soft, bluish-white metal and can be easily cut with a knife. Mercury (Hg) is known to ancient Chinese and Hindus. It was found in Egyptian tombs of 1500 B.C. It is the only common metal liquid at ordinary temperatures. Hg is known to be used in making mercury-vapor lamps. Table 2.21 summarizes some physical properties of group-IIb metals. 

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