Why are sodium (Na) and potassium (K) in the same group on the periodic table?(1 point) Responses They are both hard and brittle. They are both hard and brittle. They are both colorless. They are both colorless. They have similar atomic weights. They have similar atomic weights. They have similar reactivity. They have similar reactivity.
They have similar reactivity.
They have similar reactivity.
Sodium (Na) and potassium (K) are located in the same group on the periodic table because they have similar reactivity. To determine this, one approach is to look at the electron configuration of both elements.
Sodium, with atomic number 11, has the electron configuration [Ne] 3s^1, while potassium, with atomic number 19, has the electron configuration [Ar] 4s^1. Both elements have a single valence electron in their outermost energy level (3s^1 for sodium and 4s^1 for potassium), making them highly reactive.
Having similar valence electron configurations means that both sodium and potassium exhibit similar chemical properties. They readily lose their single valence electron to form positively charged ions (Na+ and K+) and participate in chemical reactions to fulfill the stable electron configuration of the nearest noble gas. This similarity in reactivity places them together in the same group, which is Group 1 (or Group IA) in the periodic table, commonly known as the alkali metals.