question_answer 1)

  Explain why the following compounds act as Lewis acids? (a) \[BC{{l}_{3}}\]                             (b) \[AlC{{l}_{3}}\]

Answer:

  \[\mathbf{BC}{{\mathbf{l}}_{\mathbf{3}}}\]is an electron deficient compound as the boron atom acquires six electrons in its outermost shell. It can accept a pair of electrons from a suitable donor to attain an octet configuration. Thus, \[BC{{l}_{3}}\] acts as a Lewis acid. \[AlC{{l}_{3}}\]is also an electron deficient compound and accepts alone pair from a donor and acts as a Lewis acid.