Which among the following is the most covalent compound?

1.	AlF3	2.	AlCl3
3.	AlBr3	4.	AlI3

The hybridisations of atomic orbitals of nitrogen in \(\mathrm{NO}^{+}\), \(N O_3^{-}\) and NH₃ respectively are:

1. $\mathrm{sp},$ ${\mathrm{sp}}^3$ $\mathrm{and}$ ${\mathrm{sp}}^2$

2. ${\mathrm{sp}}^2,$ ${\mathrm{sp}}^3$ $\mathrm{and}$ $\mathrm{sp}$

3. $\mathrm{sp},$ ${\mathrm{sp}}^2$ $\mathrm{and}$ ${\mathrm{sp}}^3$

4. ${\mathrm{sp}}^2,$ $\mathrm{sp}$ $\mathrm{and}$ ${\mathrm{sp}}^3$

The correct shape and hybridization for XeF₄ are:

1. Octahedral, sp³d²

2. Trigonal bipyramidal, sp³d³

3. Planar triangle, sp³d³

4. Square planar, sp³d²

Mark the correct order of repulsion among the following according to the VSEPR theory.

The decreasing order of stability of ${\mathrm{O}}_2,{\mathrm{O}}_2^{-},{\mathrm{O}}_2^{+}$ $\mathrm{and}$ ${\mathrm{O}}_2^{2-}$is: 

1. ${\mathrm{O}}_2^{+}>{\mathrm{O}}_2>{\mathrm{O}}_2^{-}>{\mathrm{O}}_2^{2-}$

2. ${\mathrm{O}}_2^{2-}>{\mathrm{O}}_2^{-}>{\mathrm{O}}_2>{\mathrm{O}}_2^{+}$

3. ${\mathrm{O}}_2>{\mathrm{O}}_2^{+}>{\mathrm{O}}_2^{2-}>{\mathrm{O}}_2^{-}$

4. ${\mathrm{O}}_2^{-}>{\mathrm{O}}_2^{2-}>{\mathrm{O}}_2^{+}>{\mathrm{O}}_2$

Which of the following species contains an equal number of $\mathrm{\sigma }$ and $\mathrm{\pi }$ bonds?

1. ${\mathrm{HCO}}_3^{-}$

2. ${\mathrm{XeO}}_4$

3. ${\left(\mathrm{CN}\right)}_2$

4. CH₂(CN)₂