question_answer 1)

  A compound (A) of boron reacts with \[NM{{e}_{3}}\] to give an adduct (B) which on hydrolysis gives a compound (C) and hydrogen gas. Compound (C) is an acid. Identify the compounds A, B and C. Give the reactions involved.

Answer:

    (A) is diborane, \[{{B}_{2}}{{H}_{6}}\]. It reacts with \[NM{{e}_{3}}\] to form an adduct (B). \[\underset{(A)}{\mathop{{{B}_{2}}{{H}_{6}}}}\,+2NM{{e}_{3}}\xrightarrow{{}}\underset{(B)}{\mathop{2B{{H}_{3}}\cdot NM{{e}_{3}}}}\,\] The (B) on hydrolysis gives boric acid,\[{{H}_{3}}B{{O}_{3}}\]. \[B{{H}_{3}}\cdot \underset{(B)}{\mathop{NMe}}\,+3{{H}_{2}}O\xrightarrow{{}}\underset{(C)}{\mathop{{{H}_{3}}B{{O}_{3}}}}\,+NM{{e}_{3}}+3{{H}_{2}}\]