Thermal Expansion by State of Matter

Steps:

• Identify that thermal expansion measures volume or length change with temperature.
• Recall solids have tightly packed particles, limiting expansion.
• Note liquids have more particle freedom than solids but less than gases.
• Determine gases expand most due to large intermolecular spaces.

Why D is correct:

• Solids have the lowest thermal expansion coefficient (α ≈ 10^{-6}/°C), liquids intermediate (α ≈ 10^{-4}/°C), and gases highest (via ideal gas law, PV = nRT, volume doubles roughly every 273°C rise).

Why the others are wrong:

• A: Reverses order; gases expand most, not least.
• B: Places gas before liquid; gases expand more than liquids.
• C: Starts with liquid; solids expand least.

Final answer: D