As you move from left to right across a period in the periodic table, how does the metallic character (reactivity of metals) change?

• A. It first increases, then decreases
• B. It remains the same
• C. It increases
• D. It decreases

Answer: (D)

Verified step by step guidance

1. Understand that metallic character refers to how readily an element exhibits properties typical of metals, such as losing electrons to form positive ions.
2. Recall that as you move from left to right across a period in the periodic table, the atomic number increases, meaning more protons and electrons are added.
3. Recognize that the effective nuclear charge (the net positive charge experienced by electrons) increases across a period, pulling electrons closer to the nucleus.
4. Because electrons are held more tightly, atoms are less likely to lose electrons, which means metallic character decreases across a period.
5. Therefore, the reactivity of metals decreases as you move from left to right across a period, confirming that metallic character decreases.