Question

The element with highest Electron Affinity among Group 16 is:

• A. O
• B. S
• C. Se
• D. Te

Hint:

In Groups 16 and 17, the 2nd element (S and Cl) always has a higher electron affinity than the 1st (O and F).

Answer 1

The Correct Option is B

Step 1: Concept Electron affinity is the energy released when an electron is added to a neutral atom.

Step 2: Meaning While electron affinity usually decreases down a group, the first element of a group often shows an anomaly.

Step 3: Analysis Oxygen has a very small atomic size. When an electron is added, it experiences significant inter-electronic repulsion from the electrons already present in the compact $n=2$ shell. Sulfur, being larger, accommodates the incoming electron more easily with less repulsion.

Step 4: Conclusion Therefore, Sulfur has a higher electron affinity than Oxygen, and it is the highest in Group 16. Final Answer: (B)