Chemical Bonding and Molecular Structure - Result Question 26
####27. Which of the following is the correct order of dipole moment?
[NEET Odisha 2019]
(a) $H_2 O<NF_3<NH_3<BF_3$
(b) $NH_3<BF_3<NF_3<H_2 O$
(c) $BF_3<NF_3<NH_3<H_2 O$
(d) $BF_3<NH_3<NF_3<H_2 O$
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Solution:
- (c) Dipole moment of a molecule is the vector sum of dipoles of bonds. So based on molecular geometry of following molecules,
Three equal vectors at $120^{\circ}$ has resultant dipole moment $=0$, so non-polar molecule
Vectors not alligned in the same direction of lone pair, so less dipole moment
Vectors alligned
in same direction moment of lone pair
