The incorrect statement among the following regarding the molecules of CH_4, NH₃, and H₂O is:

1.	The H-O-H bond angle in H2O is larger than the H-C-H bond angle in CH4.
2.	The H-O-H bond angle in H2O is smaller than the H-N-H bond angle in NH3.
3.	The H-C-H bond angle in CH4 is larger than the H-N-H bond angle in NH3.
4.	The H-C-H bond angle in CH4, the H-N-H bond angle in NH3, and the H-O-H bond angle in H2O are all greater than 90°.

Which one of the following orders is correct for the bond dissociation enthalpy of halogen molecules?

1. Cl₂ > Br₂ > F₂ > I₂

2. Br₂ > I₂ > F₂ > Cl₂

3. F₂ > Cl₂ > Br₂ > I₂

4. I₂ > Br₂ > Cl₂ > F₂

Which of the following species contains equal number of $\mathrm{\sigma }$ and $\mathrm{\pi }$ bonds?

1. ${\mathrm{HCO}}_3^{-}$                                   

2. XeO₄

3. (CN)₂                                     

4. CH₂(CN)₂

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

The total number of $\mathrm{\pi }$-bond electrons in the following structure is

1. 4       

2. 8         

3. 12         

4. 16

In which of the following pairs, both the species are not isostructural?

1. ${\mathrm{SiCl}}_4, {\mathrm{PCl}}_4^{+}$

2. Diamond, silicon carbide

3. ${\mathrm{NH}}_3, {\mathrm{PH}}_3$

4. ${\mathrm{XeF}}_4, {\mathrm{XeO}}_4$

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

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

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

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

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

A molecule having the maximum dipole moment among the following is -

1. CO₂

2. CH₄

3. NH₃

4. NF₃

Which among the following species has a triangular planar shape?

Dipole-induced dipole interactions are present in which of the following pairs?

1. H₂O and alcohol                       

2. Cl₂ and CCl₄

3. HCl and He atoms                     

4. SiF₄ and He atoms