Mendeleev’s periodic chart

Table 1,3 Mendeleev s periodic chart and electron configuration of elements. 

Manganese [7439-96-5], chemical symbol Mn, atomic number 24, and relative atomic mass 54.938049(9), is the first element of group VIIB(7) of Mendeleev s periodic chart. Its name is derived from the Latin word magnes, owing to the magnetic properties of pyrolusite... 

Tin [7440-31-5], chemical symbol Sn, atomic number 50, and relative atomic mass 118.710(7), is the fourth element of group IVA(14) of Mendeleev s periodic chart. The symbol of the element was first introduced by Berzelius, who was inspired by the Latin word for the metal, stannum, while the name of the metal comes from the Old German word zinn and the Old Norse tin. Pure tin is a silvery-white malleable and ductile dense metal with a low melting point (231.928 C) and a high boiling point (2603 C). It exhibits a low electrical resistivity (4.60 p 2.cm) and a high thermal conductivity (227 Wm K ). Tin has two allotropes ... 

The alkali metals are represented by the six chemical elements of group 1A(1) of Mendeleev s periodic chart. These six elements are, in order of increasing atomic number, lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr). The name alkali metals comes from the fact that they form strong alkaline hydroxides (i.e., MOH, with M = Li, Na, K, etc.) when they combine with water (i.e., strong bases capable of neutralizing acids). The only members of the alkali metal family that are relatively abundant in the Earth s crust are sodium and potassium. Among the alkali metals only lithium, sodium, and, to a lesser extent, potassium are widely used in industrial applications. Hence, only these three metals will be reviewed in detail in this chapter. Nevertheless, a short description of the main properties and industrial uses of the last three alkali metals (i.e., Rb, Cs, and Fr) will be presented at the end of the section. Some physical, mechanical, thermal, electrical, and optical properties of the five chief alkali metals (except francium, which is radioactive with a short half-life) are listed in Table 4.1. 

Strontium [7440-24-6], chemical symbol Sr, atomic number 38, and relative atomic mass (i.e., atomic weight) 87.62(1), is the fourth alkaline-earth metal, i.e., elements of group IIA(2) of Mendeleev s periodic chart. The word strontium comes from Strontian, a town in Scotland. Strontium is a hard, silvery-white metal when freshly cut, but it readily tarnishes in moist air, becoming yellowish due to the formation of the oxide. It resembles barium in its properties but is harder and less reactive. It has a low density (2540 kg.m" ), and a relatively... 

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