Question

Which of the following reason is correct about the statement "All members of Group IA have similar reactivity"?

• A. They have the same number of protons
• B. They have the same number of electrons
• C. They have similar outer-shell electron configurations
• D. They have valence electrons with the same quantum numbers
• E. They have the same number of neutrons

Answer 1

Answer: (C)

They have similar outer-shell electron configurations

Chemical properties generally refer to how we predict an element will react with other matter. Valence electrons or the outer shell configuration are the primary determining factor of chemical reactions, and so we would expect atoms with the same number of valence electrons to undergo the same kinds of reactions.