The electron affinity values are negative for:

A. Be-Be-, B. N-N-, C. O-O2-, D. Na-Na-, E. Al-Al-

Question

The electron affinity values are negative for:

A. Be-Be-, B. N-N-, C. O-O2-, D. Na-Na-, E. Al-Al-

Canvas Classes · Accepted Answer

Strategy:
 Electron Affinity () represents the energy change when an electron is added to a gaseous atom. A negative value (in this context, meaning endothermic) indicates energy must be supplied because the atom resists the extra electron.

Step 1: Analyze each case
- A (Be): . The fully filled -subshell is stable, and adding an electron to the  subshell is unfavorable. (Endothermic)
- B (N): . The half-filled -subshell is exceptionally stable. Adding an electron increases pairing repulsion. (E

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