Question

Dative bond is present in:
A) $N{{H}_{3}}$
B) $C{{O}_{2}}$
C) $NaCl$
D) $PC{{l}_{5}}$

Answer 1

The answer to this question is based on the calculation of total covalent bonds present in the molecule where the molecule includes the lone pair of electrons present on it too. This leads to the correct answer.

Complete step by step answer:
- Now, let us understand the base of the types of bond present between the atoms in a molecule.
- Usually, covalent bonds are present among the atoms which are basically formed by the sharing of electrons between the atoms.
- Ionic bonds are formed by the electrostatic attraction between the oppositely charged ions to form a molecule.
- Coordinate bonds which is also called dative covalent bond is a type of covalent bond wherein both the electrons come from the same atom.
- Dative bond is nothing but the dipolar bond which is in turn the coordinate covalent bond which is a kind of two centred two electron bond in which these two electrons come from the same atom.
Therefore, on the basis of these definitions, considering option A) we have ammonia which in the form of ammonium ion has a coordinate covalent bond with the fourth hydrogen atom where this hydrogen atom leaves its electrons on the chlorine atom to give the chlorine atom a negative charge. This is as shown below,
$N{{H}_{3}}+HCl\to N{{H}_{4}}^{+}+C{{l}^{-}}$

The lone pair of electrons on nitrogen shares their electron with hydrogen to form dative bonds.
On the other hand $C{{O}_{2}}$ has covalent bond and no lone pair of electrons and $NaCl$ and $PC{{l}_{5}}$ are having ionic bonds present in them.
So, the correct answer is “Option A”.

Note: The main fact to be noted here is that coordinate bond, coordinate covalent bond, dative bond or dipolar bond are all the same name given to this dative bond and not to be confused when questions are asked based on these different names.