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

1. $O_2^{+}>O_2>O_2^{-}>O_2^{2-}$

2. $O_2^{2-}>O_2^{-}>O_2>O_2^{+}$

3. $O_2>O_2^{+}>O_2^{2-}>O_2^{-}$

4. $O_2^{-}>O_2^{2-}>O_2^{+}>O_2$

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

Which of the following pairs of ions are isoelectronic and isostructural?

1. ${\mathrm{CO}}_3^{2-},$ ${\mathrm{SO}}_3^{2-}$

2. ${\mathrm{ClO}}_3^{-},$ ${\mathrm{CO}}_3^{2-}$

3. ${\mathrm{SO}}_3^{2-},$ ${\mathrm{NO}}_3^{-}$

4. ${\mathrm{ClO}}_3^{-},$ ${\mathrm{SO}}_3^{2-}$

The maximum bond angle at nitrogen is present in which of the following?

1. ${\mathrm{NO}}_2$

2. ${{\mathrm{NO}}_2}^{-}$

3. ${{\mathrm{NO}}_2}^{+}$

4. ${{\mathrm{NO}}_3}^{-}$

The correct order of bond order in the following species is:

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

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

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

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

A molecule among the following that has the maximum dipole moment is:

1. $C{O}_2$

2. $C{H}_4$

3. $N{H}_3$

4. $N{F}_3$

Which one of the following species has a plane triangular shape?

1. $N_3$^-

2. $N{O}_3^{-}$

3. $N{O}_2$^-

4. $C{O}_2$

Which among the following is an electron-deficient compound?