What are alkali and alkaline earth metals? Please explain why we call them so.

1 Answer
Jul 4, 2018

The alkali metals and alkaline earth metals form hydroxides, which are alkaline (basic), when combined with water.

Explanation:

The alkali metals and alkaline earth metals form hydroxides, which are alkaline (basic), when combined with water. The alkaline earth metals have "earth" in their name because early chemists used this designation for nonmetals that are resistant to heating and insoluble in water, which is true of their hydroxides.

Examples:

Alkali metal sodium (Na)

#"2Na(s) + 2H"_2"O(l)"##rarr##"2NaOH(aq) + H"_2("g")"#

Alkaline earth metal magnesium (Mg)

#"Mg(s) + 2H"_2"O(l)"##rarr##"Mg(OH)"_2("s") + "H"_2("g")"#