When naphthalene balls change to gaS?

Naphthalene balls change to gas through a process called sublimation, where a solid transitions directly to a gas without passing through a liquid state. This occurs when the temperature increases or when the pressure decreases, enabling the naphthalene molecules to gain enough energy to break free from the solid structure. Sublimation typically happens at room temperature under normal atmospheric conditions, which is why naphthalene is often used in mothballs. As the naphthalene sublimates, it releases a characteristic odor and can repel insects.