Sublimation is the process by which a substance transitions directly from the solid state to the gaseous state without passing through the liquid state. While many substances can undergo sublimation, not all of them do. Several factors influence whether a substance will exhibit sublimation or not:
Sublimation point: For a substance to undergo sublimation, it must have a sublimation point that is below its melting point and above its freezing point. In other words, the temperature at which the solid phase transitions to the gas phase must be higher than the temperature at which it melts to a liquid and lower than the temperature at which it freezes to a solid.
Intermolecular forces: The strength of intermolecular forces within the substance plays a crucial role in determining its phase transitions. Sublimation occurs when the attractive forces between the particles in the solid phase are not strong enough to hold them together, allowing them to break free and enter the gas phase directly. If the intermolecular forces are too strong, the substance is more likely to melt and vaporize as a liquid instead of sublimating.
Pressure and temperature conditions: Sublimation is more likely to occur at low pressures and elevated temperatures. At standard atmospheric pressure, many substances that can sublimate at higher temperatures will instead melt and evaporate as a liquid.
Examples of substances that readily undergo sublimation include dry ice (solid carbon dioxide), iodine crystals, and solid air fresheners like mothballs. On the other hand, substances like water and most metals do not undergo sublimation under normal conditions because their sublimation points are well above room temperature, and they are more likely to melt and boil instead.
In summary, whether a substance undergoes sublimation depends on its sublimation point, the strength of its intermolecular forces, and the temperature and pressure conditions it is subjected to.