Final answer:
Moth balls placed in your closet disappear due to sublimation, which is the direct transformation from solid to gas without going through the liquid phase.
Step-by-step explanation:
The best way to describe the disappearance of moth balls placed in your closet after a couple of days is sublimation. Sublimation is the transition from solid to vapor phase without going through the liquid phase. Moth balls are an example of a solid compound, such as naphthalene, that sublimates, meaning they transform from a solid directly into a gas.