Dry ice, mothballs, iodine crystals and zinc compounds are changed directly from solid to gaseous state with going into liquid state by which of the following methods?

Sublimation

The correct answer is option 4. Sublimation.

Sublimation is the process by which a substance transitions directly from the solid phase to the gaseous phase without passing through the intermediate liquid phase. This occurs when the pressure of the substance's vapor exceeds its triple point pressure and the temperature is above its sublimation point.

Dry ice (solid carbon dioxide), mothballs (naphthalene or paradichlorobenzene), iodine crystals, and certain zinc compounds are examples of substances that undergo sublimation. During sublimation, these substances absorb energy from their surroundings, causing their particles to break free from the solid lattice and enter the gas phase directly.