Question

Find the number of reaction(s) in which coordinate bond is/are formed in product side.
$B{F}_3+F^{-}\to B{F}_4^{-}$
$HF+Sb{F}_5\to HSb{F}_6$
$PC{l}_3+C{l}^{-}\to PC{l}_4{}^{-}$
$N{H}_3+H^{+}\to N{H}_4^{+}$
$H_{3}O+H^{+}\to H_4{O}^{+}$

Answer 1

In four reactions, the coordinate bond is/are formed on the product side.
These reactions are as listed below.
$B{F}_3+F^{-}\to B{F}_4^{-}$
$HF+Sb{F}_5\to HSb{F}_6$
$PC{l}_3+C{l}^{-}\to PC{l}_4^{-}$
$N{H}_3+H^{+}\to N{H}_4^{+}$
The following reaction does not involves formation of coordination bond. In fact, this reaction does not occur.
$H_3{O}^{+}+H^{+}\to H_4{O}^{+}$