Alkaline earth metals are a group of metallic elements found in the second column of the periodic table, consisting of beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). They are called "alkaline earth metals" because their oxides or hydroxides are commonly found in the Earth's crust and possess alkaline properties.
The term "alkaline" refers to their ability to form basic (alkaline) solutions when they react with water. Similarly, "earth" describes the insoluble nature of their oxides, which are reminiscent of the substances found in soil. Alkaline earth metals share certain characteristics, such as a shiny appearance, high electrical conductivity, and the ability to form ionic compounds. They have low electron affinities and low ionization energies, which means they readily lose valence electrons.
These metals exhibit similar chemical behavior due to their similar electronic configuration, with two electrons in their outermost s- orbital. This shared configuration makes them more reactive than the group 1 alkali metals but less reactive than the transition metals. They typically have a silvery-white color, good thermal conductivity, and relatively low melting and boiling points compared to other metals.
Alkaline earth metals are vital components of many materials and compounds. For instance, calcium is crucial for building and maintaining healthy bones and teeth in humans, while magnesium is involved in various cellular processes. Barium is utilized in medical imaging, and strontium is used in fireworks to produce red coloration. Some alkaline earth metals, such as magnesium and calcium, are also essential nutrients for plants.
