Practice question · Multiple choice
Molecular polarity requires both polar bonds and asymmetry to prevent vector cancellation. How does this rule distinguish the polarity of carbon tetrachloride from chloroform?
Hints
- What happens to the vector sum when one peripheral atom differs from the other three?
- Does geometric symmetry guarantee nonpolarity if the surrounding bond dipoles have different magnitudes?
Show the answer
C. A single differing bond prevents cancellation of identical dipoles
Why
Symmetry cancels identical vectors only when all surrounding positions match. Introducing a distinct substituent disrupts vector balance, whereas treating tetrahedral shapes as intrinsically nonpolar ignores how substituent identity dictates net dipole summation.
Practise Molecular Geometry and Polarity
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More questions on Molecular Geometry and Polarity
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