Why are sodium (Na) and potassium (K) in the same group on the periodic table?

Question

A. They have similar reactivity
B. They are both hard and brittle
C. They are both colorless
D. They have similar atomic weights

Answer 1

A. They have similar reactivity

Sodium (Na) and potassium (K) are both alkali metals located in Group 1 of the periodic table. They exhibit similar chemical properties and reactivity due to having the same number of electrons in their outermost shell (one electron), which makes them behave similarly in chemical reactions.