Group 1 elements are known as __________.

Group 1 elements are known as alkali metals because their oxides and hydroxides form alkaline solutions on treating with water. 

The elements in a group have the same number of valence electrons.  The group 1 elements have 1 valence electron.

The members of the group are hydrogen (H), lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr).