group 2 elements are called alkaline earth metals because of the s - block.
group 2 elements are called alkaline earth metals because of the s - block.
why group 2 elements called alkaline earth metals?
the s - block
the alkaline earth metals are named after their oxides, the "alkaline earths", whose old-fashioned names were beryllia, magnesia, lime, strontia, and baryta. these oxides are basic (alkaline) when combined with water. "earth" is an old term applied by early chemists to nonmetallic substances that are insoluble in water and resistant to heating—properties shared by these oxides. the realization that these earths were not elements but compounds is attributed to the chemist antoine lavoisier. in his "traité élémentaire de chimie" ("elements of chemistry") of 1789 he called them salt-forming earth elements. later, he suggested that the alkaline earths might be metal oxides, but admitted that this was mere conjecture. in 1808, acting on lavoisier's idea, humphry davy became the first to obtain samples of the metals by electrolysis of their molten earths, thus supporting lavoisier's hypothesis and causing the group to be named the "alkaline earth metals".
alkaline earth metal
the alkaline earth metals are all silver-colored and soft, and have relatively low densities, melting points, and boiling points. in chemical terms, all of the alkaline earth metals react with the halogens to form the alkaline earth metal halides, all of which are ionic crystalline compounds (except for beryllium chloride, which is covalent). all the alkaline earth metals except beryllium also react with water to form strongly alkaline hydroxides and, thus, should be handled with great care. the heavier alkaline earth metals react more vigorously than the lighter ones. the alkaline earth metals have the second-lowest first ionization energies in their respective periods of the periodic table because of their somewhat low effective nuclear charges and the ability to attain a full outer shell configuration by losing just two electrons. the second ionization energy of all of the alkaline metals is also somewhat low.
alkaline earth metal