Concept:Diamagnetism occurs when all electrons in a molecule's molecular orbitals are perfectly spin-paired, leaving no net magnetic field.
Formula:$$ \text{F}_2 \text{ Molecular Orbital Configuration contains ONLY paired electrons.} $$
Solution:- A fluorine atom (Group 7) has its valence electrons strictly in s and p orbitals (\( 2s^2 \ 2p^5 \)). It has no access to d-orbitals.
- When two F atoms bond to form \( \text{F}_2 \), their p-orbitals overlap to form molecular orbitals.
- All 14 valence electrons perfectly fill the bonding and antibonding molecular orbitals in pairs.
- Because all electrons residing in the p-derived molecular orbitals are paired, the molecule is repelled by magnetic fields (diamagnetic).
Why other options are incorrect:- Option A & Option C: Fluorine (Period 2) does not have d-orbitals.
- Option D: Unpaired electrons would make the molecule paramagnetic (like \( \text{O}_2 \)), not diamagnetic.
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