Answer:
Group 1 metals or the alkali metals
Step-by-step explanation:
The group 1 elements are all metals except for hydrogen, the first element in the group. Group 1 metals have one valence electron in their outermost shell. The metallic character increases as one goes down the group.
The metallic character of an element is determined by how readily it loses electrons. Elements that lose electrons most easily have the greatest metallic character. Group 1 metals have the greatest metallic character due to the ease with which they donate or lose their one valence electron. As the atomic radius increases on going down the group, their metallic character increases. Also, due to screening effect of the inner electrons on the valence electron from the positive nuclear charge of the nucleus, metallic property increases on going down the group.