Question

Which of the following can act as a Lewis base?
(1) $NCl _{3}$
(2) $PCl _{3}$
(3) $NBr _{3}$
(4) $SbCl _{3}$

• A. 1, 2 and 3 are correct
• B. 1 and 2 are correct
• C. 2 and 4 are correct
• D. 1 and 3 are correct

Answer 1

Answer: (D)

Trifluorides and trichlorides of $P$ and $Sb$ such as $PCl _{3}$ and $SbCl _{3}$ act as Lewis acid. $NCl _{3}$ and $NBr _{3}$ act as Lewis base (All trihalides of nitrogen except $NF _{3}$ act as Lewis base).