Final answer:
When a compound sublimates, its molecules move directly from the solid state to the gas state through a process called sublimation. Option A is correct..
Step-by-step explanation:
When a compound sublimates, its molecules move directly from the solid state to the gas state. This phase change is called sublimation. Sublimation is the conversion of a solid (relatively high density) to a gas (much lesser density), resulting in a greater dispersal of matter. For example, dry ice (solid carbon dioxide) sublimes directly into carbon dioxide gas without going through the liquid phase.
This phase change is called sublimation, and it occurs when the molecules within the solid gain enough energy to overcome intermolecular forces and transition into the gas phase without passing through the liquid phase. A classic example of this is dry ice, which is solid carbon dioxide (CO₂); at room temperature, it sublimes and appears to vanish as it turns into carbon dioxide gas, without forming any liquid. This process results in a greater dispersal of matter, as the molecules will occupy a much larger volume in the gas phase compared to the solid phase. Therefore, the correct answer to the question is A) From solid to gas directly.