Question

Choose the correct statements about diborane. I. It is prepared by the oxidation of sodium borohydride with iodine. II. It undergoes cleavage reactions with Lewis bases to give borane adducts. III. It is produced on an industrial scale by the reaction of \(BF_3\) with \(LiAlH_4\). IV. It is readily hydrolysed by water to give borazine. V. It burns in oxygen and gives boron trioxide.

• A. I, II, III
• B. I, II, V
• C. I, II, IV
• D. II, III, IV
• E. I, III, V

Hint:

Diborane reacts with Lewis bases and burns to give \(B_2O_3\). Hydrolysis of diborane gives boric acid, not borazine.

Answer 1

The Correct Option is B

Concept: Diborane \((B_2H_6)\) is an electron-deficient compound. It reacts with Lewis bases, is hydrolysed by water to boric acid, and burns in oxygen to give boron trioxide.

Step 1: Check statement I.
Diborane can be prepared by oxidation of sodium borohydride with iodine. Hence statement I is correct.

Step 2: Check statement II.
Diborane undergoes cleavage with Lewis bases to give borane adducts. Hence statement II is correct.

Step 3: Check statements IV and V.
Diborane does not hydrolyse to borazine; it gives boric acid. So IV is incorrect. It burns in oxygen to give \(B_2O_3\), so V is correct. Thus, the correct set is: \[ I,\ II,\ V \]