Question

How many pairs of electrons are shared between the nitrogen atoms in the triple bond of the nitrogen molecule?

Answer 1

Hint: To determine the electron pairs shared in a molecule we should know how to write the Lewis structure and how a bond forms. We can draw the Lewis structure of the nitrogen molecule to determine the electron pair that is shared between two nitrogen atoms.

Complete step by step answer:
We will write the Lewis structure as follows:
- First, we will write the basic structure. Then we will decide the central atom around which we will write all atoms of the molecule. The least electronegative atom is the central atom.
- Then we will count the total of valence electrons.
- Two electrons are used in the formation of a bond. The bond formed by sharing two electrons, one from each bonded atom is known as a single bond.
- The bond formed by sharing four electrons, two from each bonded atom is known as a double bond.
- The bond formed by sharing six electrons, three from each bonded atom is known as a triple bond.
- So, we will count the total electron used in bond formation. Then we will subtract the electrons used in bond formation from the total valence electrons.
- Then we will arrange the remaining electrons around each atom to complete the octet.
Lewis structure of ${{\text{N}}_{\text{2}}}$ ion is as follows:
Total valence electrons in ${{\text{N}}_{\text{2}}}$ are as follows:
$ = \,5 \times 2$
$ = \,10$

So, nitrogen has three shared electron pairs.
Therefore, three pairs of electrons are shared between the nitrogen atoms in the triple bond of the nitrogen molecule?

Note: Each bond forms by sharing two electrons or one electron pair so, the number of bonds represents the number of electron pairs shared between two bonded atoms. Here, in nitrogen the triple bond is present, so the number of shared electron pairs is three. We can also determine the number of electrons shared between two bonded atoms from the given type of bond. Triple bond means three electrons pair and each pair has two electrons so, the total number of electrons shared is six.