Erdalkalimetalle

Erdalkalimetalle, also known as alkaline earth metals, is a group of six chemical elements in the periodic table. They are located in Group 2 of the periodic table, positioned between the alkali metals (Group 1) and the transition metals (starting from Group 3). The elements in this group are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).

These metals are characterized by their relatively high reactivity, though they are less reactive than the alkali metals. They all possess two valence electrons, which they readily lose to form stable ions with a +2 charge. This tendency to lose electrons makes them good reducing agents. Their common electron configuration ends in ns^2, where n is the principal quantum number.

In their pure form, the alkaline earth metals are lustrous, silvery-white, and relatively soft metals, with the exception of beryllium, which is harder and more brittle. Their melting and boiling points are generally higher than those of the corresponding alkali metals. Reactivity increases as you go down the group, with barium and radium being the most reactive.

Alkaline earth metals are widely distributed in the Earth's crust. Calcium and magnesium are particularly abundant and play vital roles in biological systems. For instance, calcium is a key component of bones and teeth, and magnesium is essential for enzyme function. Compounds of these elements, such as calcium carbonate (found in rocks like limestone and marble) and magnesium oxide, are common and have numerous industrial applications. Beryllium compounds are used in alloys and in nuclear reactors due to their unique properties. Strontium and barium compounds are utilized in fireworks, glass manufacturing, and medical imaging. Radium, being radioactive, has had limited applications, primarily in historical medical treatments.