Nitrogen gas is an extremely stable molecule because of which of the following?
A.
Ionic bonds.
B.
Hydrogen bonds.
C.
Resonance bonds.
D.
Triple covalent bonds.
The Correct answer and Explanation is:
The correct answer is:
D. Triple covalent bonds.
Explanation:
Nitrogen gas (N₂) is an extremely stable molecule due to the presence of a triple covalent bond between the two nitrogen atoms. A covalent bond occurs when atoms share pairs of electrons. In nitrogen gas, the two nitrogen atoms are held together by three shared pairs of electrons, forming a triple bond. This triple bond consists of one sigma (σ) bond and two pi (π) bonds, making it one of the strongest types of chemical bonds.
The triple bond in N₂ is characterized by its high bond energy, meaning a significant amount of energy is required to break it. The bond energy of the N≡N bond is approximately 945 kJ/mol, which is higher than most other diatomic molecules. This high bond energy is a major factor in the molecule’s stability.
The stability of nitrogen gas can be understood by considering the electron configuration of nitrogen. Each nitrogen atom has five valence electrons. By sharing three pairs of electrons through the triple bond, both nitrogen atoms achieve a full octet, leading to a stable electronic arrangement. This full octet is a key reason why the molecule is so stable and inert under standard conditions.
Due to the strength of the triple bond, nitrogen gas is relatively unreactive, and breaking the N≡N bond requires significant energy. This is why nitrogen gas is commonly used as an inert atmosphere in chemical reactions where other gases might react. The stability of nitrogen gas also makes it a crucial component of Earth’s atmosphere, where it exists as about 78% of the air by volume.
In summary, the extreme stability of nitrogen gas is primarily due to the presence of the triple covalent bond between the nitrogen atoms, which requires a large amount of energy to break, making N₂ an exceptionally stable and inert molecule.