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प्रश्न
If B–Cl bond has a dipole moment, explain why BCl3 molecule has zero dipole moment.
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उत्तर १
As a result of the difference in the electronegativities of B and Cl, the B–Cl bond is polar in nature. However, the BCl3 molecule is non-polar. This is because BCl3 is trigonal planar in shape. It is a symmetrical molecule. Hence, the respective dipole-moments of the B–Cl bond cancel each other, thereby causing a zero-dipole moment.
उत्तर २
B-Cl bond has dipole moment because of polarity. In BCl3 since the molecule is symmetrical (planar). Thus the polarities cancel out.
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