Answer:
Sodium is a member of the Alkali Metals family and Calcium is part of the Alkaline Earth Metals family.
Alkali Metals characteristics: Silvery solid, very soft, low density, low melting point, extremely reactive especially in water, has 1 valence electron, reactivity increases as you go down the family.
Alkaline Earth Metals characteristics: contain 2 valence electrons, harder and denser than Alkali Metals, never found free in nature, and highly reactive.
Explanation:
Alkali Metals: Keep in mind Hydrogen is not part of the family, its just there in the same column because of the number of valence electrons in has.
