Which of the following elements exhibits the greatest metallic character and is therefore most reactive with other elements?

• A. Al (aluminum)
• B. Na (sodium)
• C. Si (silicon)
• D. P (phosphorus)

Answer: (B)

Verified step by step guidance

1. Understand that metallic character refers to how readily an element can lose electrons to form positive ions, which is related to its position on the periodic table.
2. Recall that metallic character increases as you move down a group (column) in the periodic table because atoms have more electron shells, making it easier to lose electrons.
3. Also remember that metallic character decreases as you move from left to right across a period (row) because atoms hold their electrons more tightly.
4. Identify the positions of the elements: Sodium (Na) is in Group 1 and Period 3, Aluminum (Al) is in Group 13 and Period 3, Silicon (Si) is in Group 14 and Period 3, and Phosphorus (P) is in Group 15 and Period 3.
5. Compare their metallic characters based on their group positions: elements in Group 1 (like Na) have the greatest metallic character and are most reactive, while elements further to the right have less metallic character.