We explain what the gaseous state is and some of its properties. In addition, the transformation of matter to a gaseous state and examples.
What is the gaseous state?
The gaseous state is understood as one of the four states of matter aggregation, along with the states solid, liquid Y plasmatic.
Substances in a gaseous state are called "gases" and are characterized by having their particles constitutive loosely joined together, that is, expanded throughout the container where they are, to cover as much as possible the available space.
The latter is due to the fact that the particles that make up the gases present a very slight attractive force to each other, and for this reason they do not have a shape or occupy a volume defined in the space. On the other hand, the density of gases is much smaller than that of solids and liquids, and they also have very little response to gravity.
Due to the little interaction between the gas particles, they are suspended with very little influence from the gravity (It can be said that they "float"). In addition, despite their almost zero cohesion, gases have an enormous capacity to be compressed, which is often carried out during their industrial treatment for transport.
The physical properties of a given gas (color, taste, odor) can vary depending on the elements that make it up or that are dissolved in it. For example, him air is colorless, odorless and tasteless, while hydrocarbons like methane, they have a typical unpleasant odor and can present color.
Transformation of matter to the gaseous state
It is possible to bring certain liquids or solids to the gaseous state, usually by subjecting them to sustained drastic changes in temperature me Pressure. In the same way but in the opposite direction, a gas can be transformed into a liquid or a solid. These processes can be studied separately, as follows:
- From liquid to gas: evaporation. This transformation occurs when it is administered heat to the liquid. When its most superficial particles can break the surface tension of the liquid, the substance goes into the gaseous state. Evaporation occurs gradually, so the liquid goes slowly into the gaseous phase.
- From liquid to gas: boiling. This transformation occurs when caloric energy to a liquid. When, by increasing its temperature, it reaches its boiling point (temperature at which the vapor pressure of the liquid coincides with the pressure that surrounds the liquid), all the liquid goes into the vapor phase, that is why we can see bubbles in inside the liquid. Water, for example, boils at 100ºC and turns into water vapor.
- From solid to gas: sublimation. This process occurs when a solid transforms into a gas without previously transforming into a liquid. An example is seen at the poles of the Planet, where the temperature is so low that the formation of liquid water is impossible, but even so the ice and snow are sublimated directly to the atmosphere.
- From gas to liquid: condensation. This physical process occurs when a gas turns into a liquid by decreasing its temperature (removing heat). Vaporization is the reverse process of condensation. By subtracting energy, the gas particles move slower, which allows them to interact more and, therefore, their attractive forces are greater. This is what happens in the atmosphere when, moving away from the land surface, the water steam it loses temperature and forms clouds that eventually precipitate in the form of drops of water through the phenomenon called rain.
- From gas to solid: reverse sublimation. This process occurs when, by removing heat, a gas passes to the solid state without going through the liquid state. It takes place under specific pressure conditions that subject the gas particles to a greater interaction, which causes the gas to pass to the solid state directly. An example of this is the semi-solid frost that appears on the windows of a winter day.
Examples of gaseous state
Butane gas is organic in nature.
Some everyday examples of matter in a gaseous state are:
- Water steam. When water evaporates, it changes state and turns into steam. We can check this when we cook: when certain liquids boil we can see the steam column emerging from the pot.
- Air. The air we breathe is a homogeneous mass of gases of various nature, such as oxygen, hydrogen and nitrogen, which are generally transparent, colorless and odorless.
- Butane. It is a gas of organic nature, derived from Petroleum, composed of flammable hydrocarbons. We use it to generate heat and power our kitchens, and in lighters.
- Methane. It is another hydrocarbon gas, a frequent by-product of the decomposition of the organic material. It can be found in quantities in bogs, bogs, or even in the intestines of the human being. It has a characteristic unpleasant odor.