How many covalent bonds are formed by Nitrogen?

Analyze the question: It asks how many covalent bonds a nitrogen atom typically forms.

Concept: An atom forms covalent bonds by sharing electrons until it has a stable octet (8 electrons in its outer shell). The number of bonds it forms is usually equal to the number of electrons it needs to complete that octet.

Solution:

1. Nitrogen has atomic number 7, so its electron configuration is 2, 5 (1s² 2s² 2p³).
2. It has 5 valence electrons.
3. To reach an octet, it needs 8 − 5 = 3 more electrons.
4. It does this by sharing 3 electrons, forming 3 covalent bonds.

Examples:

• Ammonia, NH₃: nitrogen forms 3 single bonds with three hydrogen atoms, and keeps one lone pair.
• Nitrogen gas, N₂: the two atoms share 3 pairs of electrons, giving a triple bond (N≡N).

Note on option D: Nitrogen can reach 4 bonds in the ammonium ion (NH₄⁺), but the fourth bond is a dative (coordinate) covalent bond, where nitrogen donates its lone pair. The normal number of covalent bonds nitrogen forms is 3.

Tip: Use the "8 minus group number" rule for non-metals. Nitrogen is in Group 5, so 8 − 5 = 3 bonds. Likewise, oxygen (Group 6) forms 2 bonds, and chlorine (Group 7) forms 1.