Compressibility distinguishes states of matter

Steps:

• Identify states: sodium chloride as solid, water as liquid, air as gas.
• Recall key property: solids and liquids resist compression due to tightly packed particles; gases compress easily due to spaced-out particles.
• Evaluate options: match sequence to solid (incompressible), liquid (incompressible), gas (compressible).
• Confirm D fits perfectly.

Why D is correct:

• Incompressibility defines solids and liquids by close particle packing (kinetic molecular theory), while gases compress via large intermolecular spaces.

Why the others are wrong:

• A: Incorrectly states liquids and gases compress easily; liquids do not.
• B: Falsely claims solids have stationary particles (they vibrate) and gases incompressible.
• C: Ignores compressibility; also wrongly says liquid particles stationary (they slide past each other).

Final answer: D