Bond strength explains reactivity differences in diatomic gases

Steps:

• Identify bond types: N₂ has a triple bond, O₂ a double bond, Cl₂ a single bond.
• Compare bond strengths: Triple bonds require more energy to break than double or single bonds.
• Assess stability: High bond energy in N₂ makes it inert; lower energies in O₂ and Cl₂ allow easier reactions.
• Evaluate options: Select statements aligning with bond energy principles.

Why D is correct:

• D states the N≡N bond energy (941 kJ/mol) exceeds O=O (498 kJ/mol) and Cl–Cl (243 kJ/mol), per bond dissociation energy data, explaining N₂'s low reactivity.

Why the others are wrong:

• A: Triple bond is strong but doesn't fully explain; reactivity ties to energy, not just bond order.
• B: All bonds (N≡N, O=O, Cl–Cl) are nonpolar due to identical atoms; polarity is irrelevant.
• C: All atoms achieve octet stability in these molecules via covalent sharing; no incomplete shells.

Final answer: D