Representative elements survey

This book offers no solutions to such severe problems. It consists of a review of the inorganic chemistry of the elements in all their oxidation states in an aqueous environment. Chapters 1 and 2 deal with the properties of liquid water and the hydration of ions. Acids and bases, hydrolysis and solubility are the main topics of Chapter 3. Chapters 4 and 5 deal with aspects of ionic form and stability in aqueous conditions. Chapters 6 (s- and p-block). 7 (d-block) and 8 (f-block) represent a survey of the aqueous chemistry of the elements of the Periodic Table. The chapters from 4 to 8 could form a separate course in the study of the periodicity of the chemistry of the elements in aqueous solution, chapters 4 and 5 giving the necessary thermodynamic background. A more extensive course, or possibly a second course, would include the very detailed treatment of enthalpies and entropies of hydration of ions, acids and bases, hydrolysis and solubility. 

For the first time in our survey of the representative elements, we encounter several that were known to the ancients. Carbon, tin, and lead have been known in elemental form for thousands of years. In the 1820s, silicon was isolated by reduction of the fluoride with potassium, while germanium (Mendeleev s eka-silicon) was found in a silver ore some 60 years later. 

The halides of the elements have been surveyed throughout our tour of the representative elements. Common methods to prepare them include (1) direct reaction of the elements, (2) reactions of oxides or hydroxides with hydrogen halides, (3) reactions of oxides or lower halides with covalent fluorides, and (4) halogen exchange reactions. Nonmetal halides usually hydrolyze to form the corresponding hydroxide, oxide, or oxoacid. Pseudohalides are anions that resemble halides in their chemical behavior. 

Panesh et al. [157] were the first to make an attempt to detect rare gas metastable atoms (RGMAs) with the aid of semiconductor sensors. The sensing element (a sensor) was represented by a sintered polycrystalline film of ZnO metastable atoms were obtained in a neon ambient by electron impact. It was shown that electrical conductivity of ZnO film irreversibly increases under the action of RGMAs. However, the signals obtained were too small and that did not allow one to utilize the sensing technique to survey the processes with participation of metastable atoms. 

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