91Ó°ÊÓ

Which of the following has tetrahedral structure and the central atom is \(s p^{3}\) hybridized? (a) \(\mathrm{BF}_{4}^{-}\) \(\square\) (b) \(\mathrm{IF}_{4}^{-}\) (c) \(\mathrm{SiH}_{4}\) \(\square\) (d) \(\mathrm{PF}_{4}^{-}\)

Which of the following molecules have a bond angle smaller than tetrahedral bond? (a) \(\mathrm{NH}_{4}^{+}\) \(\square\) (b) \(\mathrm{SiH}_{4}\) (c) \(\mathrm{NH}_{3}\) \(\square\) (d) \(\mathrm{H}_{2} \mathrm{O}\)

Identify the species which are non-planar :, (a) \(\mathrm{CH}_{3}^{+}\) \(\begin{array}{ll}\square & \text { (b) } \mathrm{NH}_{4}^{+}\end{array}\) (c) \(\mathrm{BF}_{4}^{-}\) \(\square\) (d) \(\mathrm{C}_{2} \mathrm{H}_{2}\)

The nitrogen oxide(s) that contain(s) \(\mathrm{N}-\mathrm{N}\) bond \((\mathrm{s})\) is (are): [I.I.T. 2009] (a) \(\mathrm{N}_{2} \mathrm{O}\) \(\square\) (b) \(\mathrm{N}_{2} \mathrm{O}_{3}\) 0 (c) \(\mathrm{N}_{2} \mathrm{O}_{4}\) (d) \(\mathrm{N}_{2} \mathrm{O}_{5}\) [Hint : \(\mathrm{N}_{2} \mathrm{O}: \mathrm{N}=\mathrm{N}=\mathrm{O} \leftarrow \rightarrow \mathrm{N}=\mathrm{N}-\mathrm{O}\)

Molecules with see-saw shape are : (a) \(\mathrm{XeOF}_{4}\) (b) \(\mathrm{SF}_{4}\) (c) \(\mathrm{XeOF}_{2}\) \(\square\) (d) \(\mathrm{XeO}_{2} \mathrm{~F}_{2}\)

The molecules in which the central atom is \(s p^{3} d^{2}\) hybridised are : (a) \(\mathrm{XeF}_{4}\) \(\square\) (b) \(\mathrm{XeF}_{6}\) (c) \(\mathrm{SF}_{6}\) \(\square\) (d) \(\mathrm{F}_{3}^{-}\)

Which of the following elucidate molecular ofbital theory rightly? (a) Number of \(\mathrm{MO}^{\prime}\) s are equal to the number of \(\mathrm{AO}^{\prime}\) s from which they are formed [ (b) BMO's increase electron density between the nuclei [ (c) ABMO's have a region of zero electron density \(\square\) (d) Number of electrons in BMO's are more than in ABMO's \(\square\)