Question

On moving from right to left across the period of the modern periodic table, the atomic size:

• A. increases
• B. decreases
• C. remains unchanged
• D. none of these \bigskip

Hint:

Atomic size generally decreases across a period from left to right due to an increasing nuclear charge, pulling electrons closer. However, moving from right to left reverses this trend, causing atomic size to increase.

Answer 1

The Correct Option is A

As we move from right to left across a period in the modern periodic table, the atomic size increases. This occurs because the effective nuclear charge decreases, leading to a lesser attraction between the nucleus and outer electrons, causing the atomic radius to expand.