Which of the following is the most basic oxide?

1. $A{l}_2{O}_3$

2. $S{b}_2{O}_3$

3. $B{i}_2{O}_3$

4. $Se{O}_2$

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

The number of sigma ($\mathrm{\sigma }$) and pi ($\mathrm{\pi }$) bonds in pent-2-en-4-yne is:

1.  13 $\mathrm{\sigma }$ bonds and no $\mathrm{\pi }$ bond

2.  10 $\mathrm{\sigma }$ bonds and 3 $\mathrm{\pi }$ bonds

3.  8 $\mathrm{\sigma }$ bonds and 5 $\mathrm{\pi }$ bonds

4.  11 $\mathrm{\sigma }$ bonds and 2 $\mathrm{\pi }$ bonds

Among the following, which has the maximum hydration energy?

1. OH^-

2. ${\mathrm{NH}}_4^{+}$

3. F^-

4. H⁺

Among the following oxides, which has the maximum lattice energy?
1. MgO
2. CaO
3. SrO
4. BaO

Which of the following pairs of species have similar shapes?

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. $Br{O}_3^{-} and Xe{O}_3$

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. $CO<C{O}_2<C{O}_3^{2-}$

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

The correct state of hybridisation of C₂, C₃, C₅ and C₆ of the hydrocarbon 

 is in the sequence:
1. sp, sp³, sp² and sp³
2. sp³, sp², sp² and sp
3. sp, sp², sp² and sp³
4. sp, sp², sp³ and sp²