Which of the following characteristics is shared by all alkali metals and alkaline earth metals?

• A. They are all gases at room temperature.
• B. They are all highly reactive metals found in Groups 1 and 2 of the periodic table.
• C. They all have completely filled valence electron shells.
• D. They are all nonmetals that form covalent bonds.

Answer: (B)

Verified step by step guidance

1. Identify the groups in the periodic table: Alkali metals belong to Group 1, and alkaline earth metals belong to Group 2.
2. Recall the physical state of these elements at room temperature: Both alkali metals and alkaline earth metals are solids, not gases.
3. Consider their electron configurations: Alkali metals have one electron in their outermost shell, and alkaline earth metals have two electrons in their outermost shell, so neither group has completely filled valence shells.
4. Evaluate their chemical reactivity: Both groups are known for being highly reactive metals due to their tendency to lose their valence electrons easily.
5. Recognize their chemical nature: Both alkali and alkaline earth metals are metals, not nonmetals, and they typically form ionic bonds rather than covalent bonds.