Question

Electronegativity of chlorine is less than oxygen because:

• A. Oxygen has larger size than chlorine
• B. Oxygen has smaller size and more effective nuclear charge
• C. Chlorine has higher nuclear charge
• D. Both have same electronegativity

Hint:

In general, electronegativity increases as atomic size decreases and nuclear charge increases. Oxygen is more electronegative than chlorine due to its smaller size and stronger nuclear charge.

Answer 1

The Correct Option is B

Electronegativity Explained:
Electronegativity quantifies an atom's ability to attract electrons within a chemical bond. Factors influencing this property include atomic size and effective nuclear charge (Z_eff).

Periodic Table Trends:
 • Electronegativity rises from left to right across a period.
  • Electronegativity declines from top to bottom within a group.

Oxygen Compared to Chlorine:
  - Oxygen resides in Period 2, Group 16; Chlorine is in Period 3, Group 17.
  - Oxygen's atomic radius is smaller than chlorine's.
  - Consequently, oxygen's valence electrons are nearer the nucleus, experiencing a stronger effective nuclear charge.
  - This results in oxygen exerting a stronger pull on shared electrons than chlorine.

The Accurate Explanation:
Oxygen exhibits higher electronegativity than chlorine due to its smaller size and greater effective nuclear charge.

Conclusion: Option 2: Oxygen possesses a smaller size and a greater effective nuclear charge.