Exam

JEE Advanced

Year

2009

Paper

Paper 2

Subject

Chemistry

Chapter

p Block Elements (Group 13 & 14)

JEE Advanced 2009 · Paper 2 · Chemistry · p Block Elements (Group 13 & 14)

In the reaction, 2 X+B_ 2 H_ 6 [BH_ 2 ( X)_2]^ + [BH_ 4 ]^ - The...

In the reaction, 2 $\mathrm{X}+\mathrm{B}_{2} \mathrm{H}_{6}$ \longrightarrow\left[\mathrm{BH}_{2}( \mathrm{X})_2\right]^{+}\left[\mathrm{BH}_{4}\right]^{-} The amine (s)X, is (are)

Step-by-step solution

Small amines such as $\mathrm{NH}_3 \cdot \mathrm{CH}_3 \mathrm{NH}_2$ and \left(\mathrm{CH}_3\right)_2 \mathrm{NH}$give unsymmetrical cleavage of diborane according to following reaction,$$\begin{aligned}& \mathrm{B}_{2} \mathrm{H}_{6}+2 \mathrm{NH}_{3} \longrightarrow \\ & {\left[\mathrm{H}_{2} \mathrm{~B}\left(\mathrm{NH}_{3}\right)_2\right]^{+}\left[\mathrm{BH}_{4}\right]^{-}} \\ & \end{aligned}$$Large amines, such as \left(\mathrm{CH}_3\right)_3 \mathrm{~N} give symmetrical cleavage of diborane according to following reaction,