An incorrect statement regarding resonating structures is : 

1.	The contributing structure must have the same number of unpaired electrons.
2.	The contributing structures should have similar energies.
3.	The resonance hybrid should have a higher energy than any of the contributing structures.
4.	None of the above.

Assuming that Hund's rule is violated, the bond order and magnetic nature of the diatomic molecule $B_2$ is:

The hybridization of orbitals of N atom in $N{O}_3^{-}, N{O}_2^{+, }and N{H}_4^{+}$ are respectively:

1. $sp, s{p}^2, s{p}^3$

2. $s{p}^2, sp, s{p}^3$

3. $sp, s{p}^3, s{p}^2$

4. $s{p}^2, s{p}^3, sp$

A molecule having the smallest bond angle among the following is :

Molecule/Ion that is diamagnetic in nature is: 

Which among the following does not contain a set of isoelectronic species?

1. $\mathrm{S}{{\mathrm{O}}_3}^{-2}, {\mathrm{CO}}_3^{2-}, \mathrm{N}{{\mathrm{O}}_3}^{-}$

2. ${\mathrm{CN}}^{-}, {\mathrm{N}}_2, \mathrm{CO}$

3. ${\mathrm{BO}}_3^{3-} , {\mathrm{CO}}_3^{2- },\mathrm{N}{{\mathrm{O}}_3}^{-}$

4. ${\mathrm{PO}}_4^{3-}, {\mathrm{SO}}_4^{2-}, \mathrm{Cl}{{\mathrm{O}}_4}^{-}$

A molecule or ion that has an unequal bond length is:

The correct increasing order of the polarizing power of the cationic species  ${\mathrm{K}}^{+}, {\mathrm{Ca}}^{2+}, {\mathrm{Mg}}^{2+}, {\mathrm{Be}}^{2+}$is: 

1. ${\mathrm{Be}}^{2+}<{\mathrm{K}}^{+}<{\mathrm{Ca}}^{2+}<{\mathrm{Mg}}^{2+}$

2. ${\mathrm{K}}^{+}<{\mathrm{Ca}}^{2+}<{\mathrm{Mg}}^{2+}<{\mathrm{Be}}^{2+}$

3. ${\mathrm{Ca}}^{2+}<{\mathrm{Mg}}^{2+}<{\mathrm{Be}}^{2+}<{\mathrm{K}}^{+}$

4. ${\mathrm{Mg}}^{2+}<{\mathrm{Be}}^{2+}<{\mathrm{K}}^{+}<{\mathrm{Ca}}^{2+}$

The specie with the shortest bond length is:

Among the following, the maximum covalent character is shown by which compound:

1. ${\mathrm{MgCl}}_2$

2.$$ ${\mathrm{FeCl}}_2$

3. ${\mathrm{AlCl}}_3$

4. ${\mathrm{SnCl}}_2$