The set of oxides of nitrogen that are paramagnetic in nature is:

1. NO, N₂O

2. N₂O₃, NO

3. NO, NO₂

4. N₂O, NO₂

The most preferred structure among the following with the lowest energy for SO₃ is: 

1.		2.
3.		4.

Considering the X-axis as the internuclear axis, a sigma bond will not be formed in:

$1.$ $1\mathrm{s}$ $\mathrm{and}$ $2\mathrm{s}$
$2.$ $1\mathrm{s}$ $\mathrm{and}$ $2{\mathrm{p}}_{\mathrm{x}}$
$3.$ $2{\mathrm{p}}_{\mathrm{y}}$ $\mathrm{and}$ $2{\mathrm{p}}_{\mathrm{y}}$
$4.$ $1\mathrm{s}$ $\mathrm{and}$ $1\mathrm{s}$

${\mathrm{AlCl}}_3$ $+$ ${\mathrm{Cl}}^{-}$ $\to$ ${\mathrm{AlCl}}_4^{-}$

The change in the hybridization of the Al atom in the above reaction is:
1. \(s p^{2} \text { to } s p^{3}\)
2. \(\mathrm{sp}^{3} \text { to } s p^{2}\)
3. \(\mathrm{sp}^{3} \text { to } \mathrm{dsp}{ }^{2}\)
4. \(\operatorname{sp}^{2} \text { to } d s p^{2}\)

In the option are given sequences of increasing bond order for the following species. The correct option is :
\(\mathrm{O}_2,\mathrm{N}_2,\mathrm{O}^+_2 ~\mathrm{and}~\mathrm{O}^-_2\)  

The plus and negative sign of the orbitals mean:

1. Wave function.

2. Probability density.

3. Quantum number of orbitals.

4. Frequency of orbitals.

The relative order of stability of the following species: \(\mathrm{O}_2,\mathrm{O}^+_2,\mathrm{O}^-_2~\mathrm{and}~\mathrm{O}^{2-}_2\) is -

The incorrect statement about NH₃ and H₂O is :

1. The bond angle in NH₃ is less than in H₂O.

2. Both have distorted tetrahedral geometries.

3. The bond angle in H₂O is less than in NH₃.

4. Both are sp³ hybridized. 

The shape of  AsF₅ is:
1. Pentagonal bipyramidal.
2. Trigonal bipyramidal.
3. Distorted tetrahedral.
4. Square pyramidal.

The Lewis dot symbols for atoms of the elements Mg, Na, O, and N, respectively, would be:

1.
2.
3.
4.