Question

The effective nuclear charge across the period (from left to right)

• A. Increases
• B. Decreases
• C. First increases and then decreases
• D. First decreases and then increases

Answer 1

The correct option is A Increases

As $Z_{eff}=Z_0-\text{Shielding Constant}$

The periodic table tendency for effective nuclear charge:
Increase across a period (due to increasing nuclear charge with no significant increase in shielding effect). This is because electrons are added to the same shell.