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A student leaves a camphor tablet open on a table for a week. It shrinks but there is never any liquid. Explain. Step 1: Camphor is a substance that sublimes at room temperature. Step 2: Its solid particles gain enough energy to escape directly as gas. Step 3: The liquid state is skipped because at normal pressure camphor's liquid phase is unstable. Step 4: Mass is lost as camphor vapour (with its strong smell) — no melting involved. Conclusion: the shrinking without wetness proves sublimation.