Question

Which one of the following has smaller atomic radii?

• A. Sodium (Na)
• B. Magnesium (Mg)
• C. Fluorine (F)
• D. Silicon (Si)

Hint:

Atomic radii decrease as you move from left to right across a period in the periodic table.

Answer 1

The Correct Option is C

Step 1: Trend of Atomic Radii.
Across a period from left to right, atomic radii decrease due to an increase in effective nuclear charge, which pulls the electrons closer to the nucleus. Step 2: Comparison.
Out of Sodium (Na), Magnesium (Mg), Aluminium (Al), and Silicon (Si), Fluorine (F) is located furthest to the right in the periodic table. Therefore, it has the smallest atomic radius among the given elements. Step 3: Conclusion.
Thus, Fluorine (F) has the smallest atomic radius.