Which of the following statements about diborane, B2H6, are correct?

Each boron atom is sp^3 hybridised.

It can be prepared by 4BF3 + 3LiAlH4 -> 2B2H6 + 3LiF + 3AlF3 in dry ether.

With trimethylamine it undergoes symmetrical cleavage to give BH3.N(CH3)3.

Each boron atom is sp^3 hybridised.

All six B-H bonds are of the same length and the same type.

It can be prepared by 4BF3 + 3LiAlH4 -> 2B2H6 + 3LiF + 3AlF3 in dry ether.

With trimethylamine it undergoes symmetrical cleavage to give BH3.N(CH3)3.

JEE Advanced levelOne or more correct optionsDifficulty 3 of 3pb177

Which of the following statements about diborane, $B X_{2} H X_{6}$ , are correct?

AEach boron atom is $s p^{3}$ hybridised.
BAll six $B - H$ bonds are of the same length and the same type.
CIt can be prepared by $4 BF X_{3} + 3 LiAlH X_{4} 2 B X_{2} H X_{6} + 3 LiF + 3 AlF X_{3}$ in dry ether.
DWith trimethylamine it undergoes symmetrical cleavage to give $BH X_{3} \cdot N (CH X_{3}) X_{3}$ .

Each B has four bonds (two terminal, two bridging), so it is

s p^{3}

. The

LiAlH X_{4}

route and the symmetrical cleavage by

N (CH X_{3}) X_{3}

are standard. The four terminal

B - H

bonds are 2c-2e and shorter, while the two bridge bonds are 3c-2e and longer, so the last statement is false.