Water is the most amazing substance on Earth. It is to her that we owe life, since she participates in all processes of life. Water has the most unusual properties, and scientists have not yet been able to explain all of them. For example, it turned out that she has a memory and can respond to different words. And the most famous property of water is that it is the only substance that can be in all three states of aggregation. Liquid is, in fact, water, solid is ice. We can observe the gaseous state of water constantly in the form of steam, fog or clouds. An ordinary person does not think that it is all water; he is used to calling this word only liquid. Many do not even know what the gaseous state of water is called. But it is precisely this feature of her that provides life on Earth.
Water value
This amazing moisture occupies about 70% of the Earth’s surface. In addition, it can be found at great depths - in the thickness of the earth's crust and high in the atmosphere. The entire mass of water in the form of liquid, ice and steam is called the hydrosphere. It is vital for all life forms on Earth. It is under the influence of water that climate and weather are formed all over the world. And the existence of life depends on its ability to transfer from one state of aggregation to another. This feature of it provides a water cycle in nature. Of particular importance is water in a gaseous state. This property of it helps to transfer large masses of moisture over vast distances. Scientists estimate that the Sun evaporates a billion tons of water from the Earth’s surface in a minute, which is transported to another place in the form of clouds , and then it rains.
Gaseous state of water
A feature of water is that its molecules are capable of changing the nature of the relationship with each other when the temperature fluctuates. The basic properties of it do not change. If you heat water, its molecules begin to move faster. Those that come into contact with the air break their bonds and mix with its molecules. Water in a gaseous state retains all its qualities, but also acquires the properties of a gas. Its particles are at a great distance from each other and move intensively. Most often, this condition is called water vapor. It is a colorless, transparent gas that, under certain conditions, will again turn into water. It is ubiquitous on Earth, but most often it is not visible. Examples of gaseous water are clouds, fog, or water vapor produced by boiling a liquid. In addition, it is everywhere in the air. Scientists have noticed that when it is moistened, breathing becomes easier.
What is the steam like?
Most often, the water goes into a gaseous state when the temperature changes. The usual steam, which is familiar to everyone, is formed during boiling. It is this whitish hot cloud that we call water vapor. When the liquid reaches a boiling point during heating , and at ordinary pressure this occurs at 100 ° C, its molecules begin to evaporate intensively. Getting on colder objects, they condense in the form of droplets of water. If a large amount of liquid is heated, then saturated vapor forms in the air. This is a state where gas and water coexist because the rate of evaporation and condensation is the same. In the case when there is a lot of water vapor in the air, they speak of its increased humidity. When the temperature decreases, such air intensively condenses moisture in the form of dew drops or fog. But for the formation of fog there are few special conditions of temperature and humidity. It is necessary that in the air there was a certain amount of dust, around which moisture condenses. Therefore, in cities fogs due to dust are formed more often.
Water transition from one state to another
The process of steam formation is called vaporization. Every woman observes it while cooking. But there is a reverse process, when the gas turns back into water, settling on objects in the form of tiny droplets. This is called condensation. How does vaporization most often occur? In vivo, this process is called evaporation. Water evaporates constantly under the influence of solar heat or wind. Artificially generating steam can be caused by boiling water.
Evaporation
This is the process when a gaseous state of water is obtained. It can be natural or accelerated with the help of various devices. Water evaporates constantly. From time immemorial, people have used this property of her for drying clothes, dishes, firewood or grain. Any wet object gradually dries due to the evaporation of moisture from its surface. Molecules of water in their movement one by one come off and mix with air molecules. Through observation, people understood how to accelerate this process. For this, various devices and devices were even created.
How to speed up evaporation?
1. People noticed that this process proceeds faster at high temperatures. For example, in the summer, a wet road dries instantly, which can not be said about autumn. Therefore, people dry objects in warmer places, and recently special dryers with heating have been created. And in frosty weather, evaporation also occurs, but very slowly. This property is used to dry valuable
ancient books and manuscripts, placing them in special freezers.
2. Evaporation occurs faster if the area of contact with the air is large, for example, water disappears from a plate faster than from a can. This property is used when drying vegetables and fruits, cutting them into thin slices.
3. Even people noticed that they dry out faster under the influence of wind. This is because water molecules are carried away by a stream of air, and they are not able to condense again on this object. This feature was used to create a hairdryer and air hand dryers.
Gaseous Water Properties
Water vapor is invisible in most cases. But at high temperatures, when a lot of water evaporates immediately, it can be seen in the form of a white cloud. The same thing happens in cold air, when water molecules condense in the form of tiny droplets, which we notice.
Water in a gaseous state can dissolve in air. Then they say that its humidity has increased. There is a maximum possible concentration of water vapor, which is called the "dew point". Above this limit, condensation occurs in the form of fog, clouds or dew drops.
Molecules of water in a gaseous state move very quickly, occupying a large volume. This is especially noticeable at high temperatures. Therefore, you can observe how the lid jumps when boiling at the kettle. The same property leads to the fact that when burning firewood, a crack is heard. This evaporating water breaks wood fibers.
Water vapor has elasticity. It is able to contract and expand with temperature.
Application of water vapor properties
All these properties have long been studied by people and are used for domestic and industrial needs.
- For the first time, the gaseous state of water was used in a steam engine. For many years, this was the only opportunity to set in motion vehicles and machinery in industry. Steam turbines are still in use today, and in vehicles, the gas engine has long replaced the steam engine. And now the engine can only be seen in museums.
- Everywhere and for a long time, steam has been used in cooking. Steaming meat or fish makes them tender and healthy for everyone.
- Hot steam is also used to heat homes and processes in industry. Steam heating is very effective and quickly gained popularity among the population.
- The gaseous state of water is now used in fire extinguishers of a special design, which are used to extinguish oil products and other combustible liquids. Heated steam blocks the access of air to the source of ignition, stopping combustion.
- In recent years, the gaseous state of water has been used to care for clothes. Special steamers not only smooth out delicate things, but also remove some spots.
- The use of water vapor to sterilize objects and medical instruments is very effective.
When is water vapor harmful?
There are places on Earth where water is almost always in a gaseous state. These are geyser valleys and the surroundings of active volcanoes. It is impossible for a person to be in such an atmosphere. It is difficult to breathe there, and increased humidity prevents the evaporation of moisture from the skin, which can lead to overheating. You can also burn yourself very much with the steam that forms when water boils. And fogs can reduce visibility, leading to accidents. But in all other cases, the property of water to pass into a gaseous state is used by man for his own benefit.