Why do simple molecular substances such as methane have low boiling points?
Answer and explanation
Correct answer: D. Only weak intermolecular forces must be overcome, not the covalent bonds
- Step 1: Boiling separates molecules from each other without breaking bonds inside them.
- Step 2: The intermolecular forces between methane molecules are weak, so little energy is needed.
Answer
Only weak intermolecular forces must be overcome, not the covalent bonds.
Why not the others: The covalent bonds within each molecule are weak: covalent bonds are strong and stay intact on boiling. There are no forces between the molecules at all: weak intermolecular forces do exist. The molecules contain delocalised electrons that escape easily: simple molecules have no delocalised electrons.
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