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JEE MainChemistryp Block Elements (Group 13 & 14)

An unknown gaseous compound X is prepared by treating NaBH₄ with I₂ . Compound X reacts with excess ammonia at low temperature to form an ionic adduct Y. Upon heating, compound Y decomposes to give a cyclic compound Z. Identify the correct statement regarding X, Y, or Z.

Options

  1. ACompound X undergoes symmetrical cleavage upon reaction with ammonia to form Y.
  2. BThe cationic part of compound Y contains an sp^2 hybridized boron atom.
  3. CCompound Z is an aromatic-like cyclic compound known as inorganic benzene.
  4. DIn compound X, all the B-H bonds are of equal length.

Correct answer

C. Compound Z is an aromatic-like cyclic compound known as inorganic benzene.

Step-by-step solution

The reaction of sodium borohydride with iodine produces diborane (X): 2NaBH₄ + I₂ B₂H₆ + 2NaI + H₂ Diborane (X) reacts with ammonia at low temperature to undergo unsymmetrical cleavage, forming the ionic adduct Y: B₂H₆ + 2NH₃ [BH₂(NH₃)₂]^+[BH₄]^- Upon heating, the ionic adduct Y forms borazine (Z): 3[BH₂(NH₃)₂]^+[BH₄]^- 2B₃N₃H₆ + 12H₂ Evaluating the given options: - Compound X ( B₂H₆ ) undergoes unsymmetrical cleavage with NH₃ , not symmetrical. - The cationic part of Y is [BH₂(NH₃)₂]^+ , where the boron atom forms

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