31.

The molecule having zero dipole moment is

• CH₂Cl₂

• BF₃

• NF₃

• ClF₃

Which of the following shell, form an outer octahedral complex?

• d⁴

• d⁸

• d⁶

• None of these

The calculated bond order in O${}_2^{-}$ ions is

• 1

• 1.5

• 2

• 2.5

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

Among the following compounds of boron, the species which also forms $\mathrm{\pi }$-bond in addition to σ-bonds is

• BH₃

• B₂H₆

• BF₃

• BF${}_4^{-}$

How many bonds are there in

• 18σ, 8$\mathrm{\pi }$

• 19σ, 4$\mathrm{\pi }$

• 14σ, 2$\mathrm{\pi }$

• 14σ, 8$\mathrm{\pi }$

Match the following

• (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)