Question

The type of oxide formed by the element among Li, Na, Be, Mg, B and Al that has the least atomic radius is:

• A. \( \text{A}_2\text{O}_3 \)
• B. \( \text{AO}_2 \)
• C. \( \text{A}_2\text{O} \)
• D. \( \text{A}_2\text{O}_4 \)

Hint:

The atomic radius decreases across a period from left to right due to an increase in nuclear charge, which pulls the electrons closer to the nucleus.

Answer 1

The Correct Option is A

The atomic radius generally decreases across a period from left to right due to increasing nuclear charge. Among the elements given (Li, Na, Be, Mg, B, Al), the atomic radius decreases as we move across the period from Li to Al. The element that forms the oxide with the least atomic radius is Al (aluminum), which forms \( \text{A}_2\text{O}_3 \).
Thus, the correct answer is \( \boxed{(1)} \).