Question

Find the number of reaction(s) in which coordinate bond is/are formed in product side:

Answer 1

5

Answer 2

A coordinate bond (or dative bond) is a type of covalent bond where both shared electrons are contributed by only one of the participating atoms. This typically occurs in Lewis acid-base reactions where a Lewis base (electron pair donor) reacts with a Lewis acid (electron pair acceptor).

1. $BF_3 + F^- \longrightarrow BF_4^-$:
   $BF_3$ is a Lewis acid, and $F^-$ is a Lewis base. $F^-$ donates a lone pair to the empty p-orbital of Boron in $BF_3$ to form a B-F bond. Coordinate bond is formed.

2. $HF + SbF_5 \longrightarrow HSbF_6$:
   $SbF_5$ is a strong Lewis acid. $HF$ acts as a source of $F^-$. The $F^-$ ion coordinates to $SbF_5$ to form the stable $[SbF_6]^-$ anion. The bond between Sb and the incoming F is a coordinate bond. Coordinate bond is formed.

3. $PCl_3 + Cl^- \longrightarrow PCl_4^-$:
   $PCl_3$ has a lone pair on Phosphorus, and Phosphorus has available empty d-orbitals. $Cl^-$ is a Lewis base. $Cl^-$ donates a lone pair to Phosphorus, forming a P-Cl bond and expanding Phosphorus's octet. Coordinate bond is formed.

4. $NH_3 + H^+ \longrightarrow NH_4^+$:
   $NH_3$ is a Lewis base because Nitrogen has a lone pair of electrons. $H^+$ is a Lewis acid. The lone pair on Nitrogen in $NH_3$ is donated to the empty 1s orbital of $H^+$ to form a N-H bond. Coordinate bond is formed.

5. $H_3O^+ + H^+ \longrightarrow H_4O_2^{2+}$:
   $H_3O^+$ has one lone pair remaining on the Oxygen atom. $H^+$ is a Lewis acid. The remaining lone pair on Oxygen in $H_3O^+$ is donated to the incoming $H^+$. Coordinate bond is formed.

All five reactions involve the formation of a coordinate bond in the product side.