How is frost and dew formed

Dew appears in the evening and morning time, that is, when the air temperature drops to the dew point, an air condition in which the water vapor in it reaches saturation. Saturated water vapor is in thermodynamic equilibrium and immediately condenses when in contact with a surface whose temperature is below the dew point temperature.
Dew does not appear on all objects, but only on those that quickly cool down after the sun's rays stop heating them, for example, on the grass. But at the same time, dew appears only at positive temperatures, since at negative temperatures frost is formed immediately.
Dew generation is highly dependent on the region and season. The greatest amount of dew is formed in the tropics, since the lower layers of air there have very high humidity, and dense vegetation cools quickly at night. In arid regions, dew is the main source of moisture for plants.
Not all the drops of water that can be seen on plants in the morning are dew; they are often produced by the plant itself from water obtained by the roots. Plants protect these drops leaves and flowers from sunlight.
Frost usually forms on horizontal, rough surfaces if they are colder than air and have a negative temperature. During the formation of frost, the process of desublimation occurs, that is, water vapor passes from the gaseous state to the solid state.