Question

Which of the following can act as a Lewis base?
(1) $NC{l}_3$
(2) $PC{l}_3$
(3) $NB{r}_3$
(4) $SbC{l}_3$

• 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 $PC{l}_3$ and $SbC{l}_3$ act as Lewis acid. $NC{l}_3$ and $NB{r}_3$ act as Lewis base (All trihalides of nitrogen except $N{F}_3$ act as Lewis base).