The Periodic Table

Question 1

Explain how the number of valence electrons of the Group 1 alkali metals makes them highly reactive.

Answer 1

Group 1 alkali metals all have one valence electron in their outermost shell. Because atoms prefer to have full outer shells (which is more stable), these substances easily lose that one electron to achieve a stable, full outer shell.

Since it takes very little energy for them to lose that single valence electron, they react quickly and strongly with other substances, such as water or oxygen, to form compounds.