The alkaline earth metals are a group of elements on the periodic table that contain two electrons in their outermost energy levels and exhibit similar characteristics such as high reactivity. This group of elements consists of beryllium, magnesium, calcium, strontium, barium and radium.
Alkaline earth metals are almost as reactive as their neighbors on the periodic table, the alkali metals. Like the alkali metals, the alkaline earth metals are soft metals that are not found in their free forms in nature.
These metals readily lose their two outer electrons to other atoms. When the alkaline earth metals lose their outermost or valence electrons, they take on a net positive charge. These atoms are now called ions; these positive ions form ionic bonds with negatively charged ions that have taken on the extra electrons from the alkaline earth metals.