Researchers create morphing crystals powered by water evaporation

Water evaporation, as observed when a puddle of water disappears on a summer day, is a remarkably powerful process. If it were harnessed, the process could provide a clean source of energy to power mechanical machines and ...

Changes in land evaporation shape the climate

Accurate estimation of how much water is evaporated from the vegetated land surface is a challenging task. A physical-based method—such as the complementary relationship (CR) of evaporation, which explicitly accounts for ...

Image: Atacama minerals

The Copernicus Sentinel-2 mission takes us over part of Chile's Atacama Desert, which is bound on the west by the Pacific and on the east by the Andes. The Atacama is considered one of the driest places on Earth—there are ...

Researchers solve a scientific mystery about evaporation

Evaporation can explain why water levels drop in a full swimming pool, but it also plays an important role in industrial processes ranging from cooling electronics to power generation. Much of the global electricity supply ...

Polluted wastewater in the forecast? Try a solar umbrella

Evaporation ponds, which are commonly used in many industries to manage wastewater, can span acres, occupying a large footprint and often posing risks to birds and other wildlife. Yet they're an economical way to deal with ...

Plants model more efficient thermal cooling method

When drops of water touch the surface of a lotus flower leaf, they form beads and roll off, collecting dust particles along the way. In contrast, water droplets on a rose petal also form beads, but remain pinned to the petal's ...

Did early mammals turn to night life to protect their sperm?

Humans are diurnal—we are active in the day and sleep at night. But diurnalism is by far the exception rather the rule in mammals. About 250-230 million years ago, the mammalian ancestors, called the therapsids, became ...

Keeping cool with quantum wells

University of Tokyo researchers have announced a new approach for electrical cooling without the need for moving parts. By applying a bias voltage to quantum wells made of the semiconductor aluminum gallium arsenide, electrons ...

Desalinating water in a greener and more economical way

We know that excessive consumption, industrial activity and growth in the global population are some of the factors threatening access to drinking water for an increasing proportion of people around the world. According to ...

Millions of Australian homes struggling in record-breaking heat

Australians left with soaring energy bills in the wake of a scorching summer are about to face another harsh reality: the vast majority of the nation's houses do not meet the current minimum energy performance requirements.

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Evaporation

Evaporation is a type of vaporization of a liquid that occurs only on the surface of a liquid. The other type of vaporization is boiling, which, instead, occurs on the entire mass of the liquid.

On average, the molecules in a glass of water do not have enough heat energy to escape from the liquid. With sufficient heat, the liquid would turn into vapor quickly (see boiling point). When the molecules collide, they transfer energy to each other in varying degrees, based on how they collide. Sometimes the transfer is so one-sided for a molecule near the surface that it ends up with enough energy to 'escape' (evaporate).

Liquids that do not evaporate visibly at a given temperature in a given gas (e.g., cooking oil at room temperature) have molecules that do not tend to transfer energy to each other in a pattern sufficient to frequently give a molecule the heat energy necessary to turn into vapor. However, these liquids are evaporating. It is just that the process is much slower and thus significantly less visible.

Evaporation is an essential part of the water cycle. Solar energy drives evaporation of water from oceans, lakes, moisture in the soil, and other sources of water. In hydrology, evaporation and transpiration (which involves evaporation within plant stomata) are collectively termed evapotranspiration. Evaporation of water occurs when the surface of the liquid is exposed, allowing molecules to escape and form water vapor, this vapor can then rise up and form clouds.

This text uses material from Wikipedia, licensed under CC BY-SA