Among the following, the compound that is electron deficient is:

1. BaCl₂

2. BCl₃

3. CCl₄

4. PCl₅

d$\mathrm{\pi }$ - p$\mathrm{\pi }$ bond is present in:

1. $C{O}_3^{2-}$

2. $P{O}_4^{-3}$

3. $N{O}_3^{-}$

4. $N{O}_2^{-}$

The compound that forms linear polymer due to H-bond is:

The correct order of dissociation energy of N₂ and N₂⁺ is:

Among the options given below, identify the Isoelectronic species:

1. CO, CN^–, NO⁺, C₂^2–

2. CO^–, CN, NO, C₂^–

3. CO⁺, CN⁺, NO^–, C₂

4. CO, CN, NO, C₂

A species that does not exhibit paramagnetism is:

1. N₂⁺

2. O₂^–

3. CO

4. NO

Among the following, the pair in which the two species are not isostructural is:

1. ${\mathrm{IO}}_3^{-}\text{and }{\mathrm{XeO}}_3$

2. ${\mathrm{BH}}_4^{-}\text{and }{\mathrm{NH}}_4^{+}$

3. ${\mathrm{PF}}_6^{-}\text{and }{\mathrm{SF}}_6$

4. ${\mathrm{SiF}}_4\text{ and }{\mathrm{SF}}_4$

Increasing order of bond length is:

1. $N{O}^{-}$ $<$ $NO$ $<$ $N{O}^{+}$ $<$ $O_2^{-}$

2. $O_2^{-}$ $<$ $NO$ $<$ $N{O}^{-}$ $<$ $N{O}^{+}$ $$

3. $O_2^{-}$ $<$ $N{O}^{-}$ $<$ $NO<$ $N{O}^{+}$ $$

4. $N{O}^{+}$ $<$ $NO$ $<$ $N{O}^{-}$ $<$ $O_2^{-}$

H₂O is dipolar, whereas BeF₂ is not. It is because:
 

In a regular octahedral molecule, MX₆, the number of X–M–X bonds at 180º is: