Question

Which of the following is the correct order of increasing atomic size?

• A. \( \text{Na} < \text{Mg} < \text{Al} \)
• B. \( \text{Na} > \text{Mg} > \text{Al} \)
• C. \( \text{Mg} < \text{Na} < \text{Al} \)
• D. \( \text{Al} < \text{Na} < \text{Mg} \)

Hint:

As you move across a period from left to right, the atomic size decreases due to increasing nuclear charge.

Answer 1

The Correct Option is B

Across a period from left to right in the periodic table, atomic size diminishes due to an increase in effective nuclear charge, which draws electrons nearer to the nucleus.Consequently, the sequence of increasing atomic size is as follows:\[\text{Na} > \text{Mg} > \text{Al}\]Therefore, atomic size decreases sequentially from sodium (Na) to magnesium (Mg) to aluminum (Al).