The correct order of C-O bond length among CO, ${\mathrm{CO}}_3^{2-}$ , CO₂ is:

1. $C{O}_2<C{O}_3^{2-}<CO$

2. $CO<C{O}_3^{2-}<C{O}_2$

3. $C{O}_3^{2-}<C{O}_2<CO$

4. $CO<C{O}_2<C{O}_3^{2-}$

In which of the following pairs, the two species are iso-structural?

1. $S{F}_4 and Xe{F}_4$

2. $S{O}_3^{2-} and N{O}_3^{-}$

3. $B{F}_3 and N{F}_3$

4. $Br{O}_3^{-} and Xe{O}_3$

In which of the following molecules are all the bonds not equal?

Which of the following species has a linear shape?

1. $N{O}_2^{-}$

2. $S{O}_2$

3. $N{O}_2^{+}$

4. $O_3$

Which of the following is not a correct statement?

The number of unpaired electrons in a paramagnetic diatomic molecule of an element with atomic number 16 is:

1. 2

2. 3

3. 4

4. 1

Which of the following is not isostructural with SiCl₄?

1. $SC{l}_4$

2. $S{O}_4^{2-}$

3. $P{O}_4^{3-}$

4. $N{H}_4^{+}$

A diatomic molecule, among the following species, that only has $\mathrm{\pi }$ bonds according to the Molecular Orbital Theory (MOT) is:

The correct order of increasing bond order among the given is:

1. ${\mathrm{O}}_2^{-}$ $<$ $\mathrm{NO}$ $<$ ${\mathrm{C}}_2^{2-}$ $<$ ${\mathrm{He}}_2^{+}$

2. $\mathrm{NO}$ $<$ ${\mathrm{C}}_2^{2-}$ $<$ ${\mathrm{O}}_2^{-}$ $<$ ${\mathrm{He}}_2^{+}$

3. ${\mathrm{C}}_2^{2-}$ $<$ ${\mathrm{He}}_2^{+}$ $<$ $\mathrm{NO}$ $<$ ${\mathrm{O}}_2^{-}$

4. ${\mathrm{He}}_2^{+}$ $<$ ${\mathrm{O}}_2^{-}$ $<$ $\mathrm{NO}$ $<$ ${\mathrm{C}}_2^{2-}$