The bond dissociation energy of B – F in BF₃ is 646 kJ mol^–1 , whereas that of C – F in CF₄ is 515 kJ mol^–1. The correct reason for the higher B-F bond dissociation energy as compared to that of C-F is :

1. Smaller size of B-atom as compared to that of C-atom

2. Stronger σ bond between B and F in BF₃ as compared to that between C and F in CF₄

3. Significant pπ − pπ interaction between B and F in BF₃ whereas there is no possibility of such interaction between C and F in CF₄

4. Lower degree of pπ − pπ interaction between B and F in BF₃ than that between C and F in CF₄

In the structure of silicon dioxide:

The structure of diborane (B₂H₆) contains:

In view of the signs of ${∆}_{\mathrm{r}}\mathrm{G}°$ for the following reactions:

$\begin{array}{l}{\mathrm{PbO}}_2+\mathrm{Pb}\to 2\mathrm{PbO},{\mathrm{\Delta }}_{\mathrm{r}}{\mathrm{G}}^{\circ }<0\\ {\mathrm{SnO}}_2+\mathrm{Sn}\to 2\mathrm{SnO},{\mathrm{\Delta }}_{\mathrm{r}}{\mathrm{G}}^{\circ }>0\end{array}$

The oxidation states more characteristic for lead and tin are respectively:

1. For lead +2, for tin +2

2. For lead +4, for tin +4

3. For lead +2, for tin +4

4. For lead +4, for tin +2 

Which one of the following boron anions cannot be formed?

1. BF₆³⁻

2. BH₄⁻

3. B(OH)₄⁻

4. BO₃^3-

Which among the following halides is inert towards hydrolysis?

1. BF₃

2. SiCl₄

3. PCl₅

4. SF₆

Aluminium chloride exists as dinner, Al₂Cl₆ in the solid state as well as in the solution of non-polar solvents such as benzene. When dissolved in acidified aqueous solution, it gives:

1. \(\mathrm{Al}^{3+}+3 \mathrm{Cl}^{-}\)

2. \(\left[\mathrm{Al}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}+3 \mathrm{Cl}^{-} \)

3. \(\left[\mathrm{Al}(\mathrm{OH})_{6}\right]^{3-}+3 \mathrm{HCl}\)

4. \(\mathrm{Al}_{2} \mathrm{O}_{3}+6 \mathrm{HCl}\)

The correct statement about B₂H₆ is:

Given below are two statements:

In the light of the above statements, choose the most appropriate answer from the options given
below.

1. Statement I is true but Statement II is false

2. Both Statement I and Statement II are false

3. Statement I is false but Statement II is true

4. Both Statement I and Statement II are true

The C–C bond length is maximum in:

1. C₆₀

2. Diamond

3. Graphite

4. C₇₀