Evaporation Essay

Evaporation is the process in which a liquid turns to a vapor without its temperature reaching boiling point. The rate of evaporation rises if the liquid is warmed up. The temperature of a liquid decreases as it evaporates because the evaporating molecules remove energy from the liquid. ¨Water is the most ordinary substance on Earth. It covers 70 percent of the world’s surface. Each water molecule is made up of two atoms of hydrogen and one of oxygen. Water freezes at 32°F (0°) and boils at 212°F (100°). Ninety-seven percent of Earth’s water is in the oceans and two percent is in the form of ice or snow. Movement of water around the Earth is called the water cycle. Water vapor in the atmosphere condenses to fall as rain, flows through rivers

¨Evaporation is the primary pathway that water moves from the liquid state back into the water cycle as atmospheric water vapor. A very small amount of water vapor enters the atmosphere through sublimation. Sublimation is the process by which water changes from a solid to a gas, bypassing the liquid phase. The process of evaporation removes heat from the environment, which is why water evaporating from your skin cools you¨. Evaporation is all about the energy in single molecules, not about the average energy of a system. The average energy can be low and the evaporation still continues. All liquids can evaporate at room temperature and normal air pressure. Evaporation is one of the two forms of vaporization. It is the process whereby atoms or molecules in a liquid state (or solid state if the substance sublimes) gain sufficient energy to enter the gaseous state. It is the opposite process of condensation. Therefore evaporation proceeds more quickly at elevated temperature, at higher flow rates between the gaseous and liquid phase and in liquids with lower surface tension. All liquids evaporate when some of their molecules/atoms fly off the surface into the nearby