Alkaline earth metals are not as active as alkali metals because they have two outermost electrons, but they are more active than other metals. Alkaline earth metals have low melting points and densities. They are good conductors of heat and electricity, ductile, malleable, and have a silver-like luster.

Magnesium has two electrons in its outermost layer; they are not as active as alkali metals but more active than other metals. Magnesium can react with oxygen, water, acids, halogens and carbon dioxide.

Magnesium is abundant in ores and seawater where magnesium chloride is extracted. Magnesium metal can be obtained by electrolyzing melted magnesium chloride.

Calcium has the same number of outer electrons as magnesium, both having two, so their chemical properties are very similar. However, calcium has a larger atomic radius, and the nucleus has less attraction to the outermost electrons, making calcium more reactive than magnesium.

Calcium is a reducing metal that does not exist in nature as a elementary substance. It usually forms compounds with other substances, such as calcium oxide, calcium hydroxide and calcium carbonate.