Concept: Covalent bonding involves the sharing of electrons between atoms to achieve a stable electron configuration, typically an octet. The number of electrons involved in bond formation refers to the total number of shared electrons in all covalent bonds between the atoms.

Why (D) is correct:

The nitrogen molecule (N\u2082) consists of two nitrogen atoms. Each nitrogen atom has an atomic number of 7, meaning its electronic configuration is 1s\u00b2 2s\u00b2 2p\u00b3. To achieve a stable octet, each nitrogen atom needs 3 more electrons. They achieve this by sharing three pairs of electrons, forming a triple covalent bond between them.

The Lewis structure for N\u2082 is:

$$:N\equiv N:$$

In this structure, the triple bond (\u2261) represents three shared pairs of electrons. Therefore, the total number of electrons involved in the bond formation is $3\times 2=6$ electrons.

Option Analysis:

• A) 2: This would correspond to a single bond, which is not present in N\u2082.
• B) 4: This would correspond to a double bond, which is not present in N\u2082.
• C) 10: This is the total number of valence electrons in two nitrogen atoms (5 valence electrons per N atom, so $2\times 5=10$), but not the number of electrons involved in bond formation.
• D) 6: This correctly represents the three shared pairs of electrons in the triple bond of N\u2082.

Correct Answer: (D)