MCQ
Which bond angle $\theta $ would result in the maximum dipole moment for the triatomic molecule $YXY$
- ✓$\theta = {90^o}$
- B$\theta = {120^o}$
- C$\theta = {150^o}$
- D$\theta = {180^o}$
✓
Answer
Correct option: A.
$\theta = {90^o}$
(a) The dipole moment of two dipoles inclined at an angle $\theta $ is given by the equation $\mu = \sqrt {{X^2} + {Y^2} + 2XY\cos \theta } $
$\cos 90^o = 0$. Since the angle increases from $90 - 180$, the value of $\cos \theta $ becomes more and more $-ve$ and hence resultant decreases. Thus, dipole moment is maximum when $\theta = 90^o $.
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