The correct order of decreasing dipole moment of (I) toluene, (II) m-dichlorobenzene (III) o-dichlorobenzene and (IV) p-dichlorobenzene is
IV < II < I < III
IV < I < II < III
I < IV < II < III
IV < I < III < II
B.
IV < I < II < III
Dipole moment of p-dichlorobenzene is zero, while that of o-dichlorobenzene is 2.54 D and for m-dichlorobenzene is 1.48 D. This shows that benzene ring is planar and in p-C6H4Cl2 two C-Cl bonds are directed in the plane of the ring, thus on adding, they becomes zero. In this, two C-Cl bonds contain an angle of 60° and in m- C6H4Cl2 the two C-Cl bonds contain an angle of 120° and their dipole moments on vector addition give a higher value of dipole moment.
Therefore, sequence of dipole moment is as follows:
p-dichlorobenzene < toulene < m-dichlorobenzene < o-dichlorobenzene
Among the following compounds of boron, the species which also forms -bond in addition to σ-bonds is
BH3
B2H6
BF3
BF
Match the following
List I | List II |
(a) PCl3 | (i) Square planar |
(b) BF3 | (ii) T-shape |
(c) ClF3 | (iii) Trigonal pyramidal |
(d) XeF4 | (iv) See- saw |
(v) Trigaonal planar |
(a) (b) (c) (d)
(iv) (ii) (i) (iii)
(a) (b) (c) (d)
(iii) (v) (ii) (iv)
(a) (b) (c) (d)
(iii) (v) (ii) (i)
(a) (b) (c) (d)
(iii) (v) (ii) (v)