The group of very reactive metals is called the alkali metals.

These metals are located in Group 1 of the periodic table. They are highly reactive because they have only one electron in their outermost shell, which they readily lose to form positive ions. This makes them highly reactive with water, oxygen, and other elements.

Here are some examples of alkali metals:

* Lithium (Li)

* Sodium (Na)

* Potassium (K)

* Rubidium (Rb)

* Cesium (Cs)

* Francium (Fr)