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Molecules of water can become gaseous wherever they are exposed to the atmosphere, as some molecules may have enough energy to leave the surface. Water vapor molecules can likewise return to the liquid state. But the rate of each phase change is dependent on the temperature.
Water is stable at temperatures between 32 and 212 degrees Fahrenheit, at which temperatures water respectively freezes and boils. We are more concerned here with temperatures at which water boils, or at least turns gaseous.
Basic Chemistry:
All molecules are made up of atoms in different combinations. All atoms 'vibrate' at different speeds depending upon their temperature (and other factors we needn't go into here). The hotter the temperature, the faster the atoms vibrate. At 212 F, the bonds holding the water molecules together become unstable and the molecules separate.
Just a small note here. Most people think what they see over boiling water is steam, it is not. It is water vapor, water molecules that have not quite reached temperature sufficient to break the bonds.
(A more complete answer explaining the vaporization mechanism can be found at the related question titled "What happens to water molecules when water is heated?".)
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The change of water from a gas to a liquid?
The process of changing liquid water into a gas is called evaporation. Energy is added to the liquid water - generally in the form of heat. When enough energy is added, it allows the most energetic molecules at the surface of the liquid to break free of the liquid and enter the gas phase. The more energy that is added, the more water molecules will have enough energy to move into the gas phase. If enough energy is added, all the molecules will leave the liquid and from then on adding energy will just make the gas warmer. Another way to change liquid water into gas is to drop the pressure above the liquid. In this case, it takes less energy for the molecules in the liquid to get away from the liquid so some of them will already be energetic enough to get away. Any mass of liquid water will have a range of energies for the molecules, some will be low energy, others high energy with each collision between the molecules, they either gain or loose energy. If they gain enough energy, they can become energetic enough to escape the liquid as a gas. The higher the pressure, the more energy is required to become a gas. If the liquid water is in contact with some gas - air for example. The liquid will evaporate until the gas is saturated with water vapor. At that point the rate of water molecules dropping out of the gas back into the water (because they don't have enough energy to stay in the gas) is equal to the rate of water molecules escaping from the liquid to become gas. This point is also known as "equilibrium".
How do liquids cool as they evaporate?
Yes - the energy to evaporate the liquid comes from the remaining liquid - which results in it cooling down. That's why when you are wet and a breeze blows over you, you feel colder as the water on you evaporates (unless the air is already so saturated with water that no evaporation can occur)
Describe three conditions necessary for condensation to occur?
They are: The temperature has to be lowered so that more molecules will go from gas to liquid than from liquid to gas. There must be tiny "seeds" or nuclei on which liquid molecules can collect. Lacking these, water can in some cases be supercooled below the freezing point.
What are some good questions for water evaporation?
it could be " how does water evaporate? " or " when is evaporation formed? "
What is the definition for liquid solid and gas?
They are the three states of matter for all substances. A solid has molecules packed tightly together; a liquid has molecules that have some room to move; gases have molecules that can move freely. eg for water the solid state is ice, the liquid state water and the gas state water vapour (steam)
What cause liquid water to evaporate?
The continuous movement of water molecules can lead some molecules at the surface to escape in the atmosphere as a gas.
When you put water in a pan what happens?
Water evaporates at any temperature. Some water molecules have enough energy to leave the surface of the liquid. As the temperature increases more and more molecules have enoughenergy to leave the surface of the liquid. At the boiling point all molecules have enough energy to evaporate. Bubbles of vapour form throughout the liquid (we see these bubbles as proof of boiling).
How do the particles of water evaporate in an open container?
When the kinetic energy of water molecules is sufficient some molecules can escape in the atmosphere.
Why does alcohol evaporate?
Some molecules at the surface of liquid gain sufficient energy to escape being transformed in a gas.
What causes of the water to evaporate?
The intermolecular forces between water molecules are lowered at the water surface and some molecules escape in the atmosphere. Evaporation is increased by temperature.
Can carbon dioxide evaporate mixed with water?
The carbon dioxide released from water can train to atmosphere some water molecules.
What best describes how water evaporate?
The energy of water molecules increase by a temperature increase and some molecules at the surface can escape in the atmosphere. But water is evaporated at any temperature.
Why the water evaporate and it will condensation?
The continuous movement of water molecules can lead some molecules at the surface to escape in the atmosphere as a gas; condensation is the inverse phenomenon of evaporation.
Water changing from a liquid to a gas?
Water changes from a liquid to a gas by evaporation. At any instant, some of the water molecules are more energetic than others, and these are able to evaporate. It is quite instructive to watch a small quantity of water evaporate when under a small vacuum. 'Boiling' away first, then freezing, but all continuing to evaporate.
What causes water to evaporate in the water cycle?
Evaporation occurs when molecules of a liquid (such as water) leave the liquid and become suspended in the air. Liquids are constantly losing molecules to the air at all temperatures, and some may be returned to the liquid from the air as they lose energy. However, the addition of heat energy can increase the rate of evaporation by exciting more of the molecules in the liquid.At what is known as the "boiling point", most or all of the molecules will have enough energy to leave the liquid. If the air above has the capacity to absorb it, the liquid's molecules will eventually all be held in the air. If the air cools, reducing the energy of the molecules and the air's ability to hold them, the molecules may return to a liquid state, in the process called condensation.
Why H2SO4 is hygroscophic?
There are some gaps among molecules of liquid sulphuric acid where it may absorb the water molecules so it is a hygroscopic liquid.
Explain Why water can evaporate from puddles even on cold days?
Because as the water molecules get heated by the sun they start to move faster and faster until they escape from the liquid and become a gas (water vapour). On a cold day or a dau without sun, this process is slower becasue the molecules move slower and find it more difficult to escape from the liquid.
