Concept:A zero dipole moment exists when a molecule is structurally symmetrical, allowing polar bond vectors to completely cancel one another.
Formula:$$ \text{O} \xleftarrow{ \ \ } \text{C} \xrightarrow{ \ \ } \text{O} $$
Solution:- Carbon dioxide (\( \text{CO}_2 \)) consists of a central Carbon atom double-bonded to two Oxygen atoms.
- Carbon has no lone pairs, resulting in a strictly linear geometry (180°).
- The two highly polar C=O bonds pull electron density equally in opposite directions. The vector sum of these forces is exactly zero.
Why other options are incorrect:- Option A & Option D: Ammonia (pyramidal) and Water (bent) have lone pairs that destroy symmetry, resulting in strong net dipoles.
- Option C: Hydrogen fluoride is a diatomic molecule with unequal electronegativities, making it inherently polar.
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