Alkaline earth metals have a valency of 2

Alkaline earth metals have a valency of 2.

Alkaline earth metals are located in group 2 of the , which implies that they each have 2 electrons in their outermost shells.

The electrons located in the outermost shell of an atom are called .

Alkaline earth metals will readily react to give up those two electrons in order to gain a complete , which is characterized by the presence of 8 electrons in the outermost shell.

Berylium is an exception to this; since it doesn't have enough electrons to be able to obtain a complete octet, berylium will lose those two in order to form a stable duet configuration.

The of the group 2 elements reveals the two each of those atoms have.

As you can see, in order to form a complete octet (or duet as mentioned earlier), every one of these atoms will give up the two electrons located in their outermost shells to form 2+ cations.

The valency of the alkaline earth metals is thus said to be 2, meaning that they each have two valence electrons.