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20: Periodic Trends and the s-Block Elements

  • Page ID
    24500
    • 20.1: Introduction
    • 20.2: Overview of Periodic Trends
      The chemistry of the third-period element in a group is most representative of the chemistry of the group because the chemistry of the second-period elements is dominated by their small radii, energetically unavailable d orbitals, and tendency to form π bonds with other atoms.
    • 20.3: The Chemistry of Hydrogen
      Hydrogen can lose an electron to form a proton, gain an electron to form a hydride ion, or form a covalent bond or polar covalent electron-pair bond. The three isotopes of hydrogen—protium (1H or H), deuterium (2H or D), and tritium (3H or T)—have different physical properties. Deuterium and tritium can be used as tracers, substances that enable biochemists to follow the path of a molecule through an organism or a cell.
    • 20.4: The Alkali Metals (Group 1)
      The alkali metals are potent reductants whose chemistry is largely that of ionic compounds containing the M+ ion. Alkali metals have only a weak tendency to form complexes with simple Lewis bases. The first alkali metals to be isolated (Na and K) were obtained by passing an electric current through molten potassium and sodium carbonates. The alkali metals are among the most potent reductants known; most can be isolated by electrolysis of their molten salts.
    • 20.5: The Alkaline Earth Metals (Group 2)
      Group 2 elements almost exclusively form ionic compounds containing the M2+ ion, they are more reactive toward group 15 elements, and they have a greater tendency to form complexes with Lewis bases than do the alkali metals. Pure samples of most of the alkaline earth metals can be obtained by electrolysis of the chlorides or oxides. Beryllium was first obtained by the reduction of its chloride; radium chloride, which is radioactive, was obtained through a series of reactions and separations.
    • 20.6: The s-Block Elements in Biology
    • 20.E: Periodic Trends and the s-Block Elements (Exercises)

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