CONDENSATION: CONCEPT, PROCESS, EXAMPLES - SCIENCE - 2025

The condensation is the physical change of a substance from the gaseous to the liquid state. This is a reverse process to vaporization. Condensation is also defined as the deposition of a vapor in liquid form on a surface colder than that of the gas.

Although condensation is a phenomenon that can occur with many substances, it is often referred to as water's own behavior. In this order of ideas, condensation is defined as the process by which water vapor is transformed into liquid water.

Condensation is seen daily on the surface of bottles or glassware with cold liquids. Source: Pixabay.

The term condensation is used with other connotations, so in chemistry the condensation reaction is one in which two small molecules join to form a larger molecule, with the loss of a molecule of water, carbon dioxide, ammonia or nitrogen..

Meanwhile, DNA condensation refers to the nucleic acid molecule adopting a more compact form during cell duplication (mitosis).

Condensation process

The passage of water from the gas phase to the liquid phase can be explained by a decrease in the temperature of the water vapor, and by an increase in its pressure.

As the temperature decreases, the kinetic energy of the gaseous water molecules in motion decreases. This slows down the water molecules and allows greater interaction between them, revealing intermolecular forces.

Among these forces are: dipole-dipole, hydrogen bridges and London dispersive forces.

The intermolecular forces bring the water molecules present in the water vapor closer together, producing their condensation; that is, the change of state from the gas phase to the liquid phase.

The other way to explain condensation is an increase in the saturation of water vapor. This is related to an increase in the pressure of the water vapor. This saturation brings about a closer relationship between the water molecules that form the steam, with more interactions between them.

Water vapor saturation occurs in clouds prior to rain, and is a mechanism that explains the condensation of water.

Dew point

It is the temperature at which the condensation of water vapor occurs. If its temperature falls below this limit, the change from the gas phase to the liquid phase will occur, as happens during nights when there is a drop in temperature.

The surfaces of cars, windows, leaves, etc., cool down and in the layers of air close to them, there is a drop in temperature that causes condensation of the air that is deposited on the surfaces, constituting what is known like dew.

Cloud condensation

In the clouds, liquefaction begins due to the formation of water droplets within them. This phenomenon is spontaneous when the relative humidity of the clouds exceeds 100%. The formation of raindrops precedes rain or snowfall when the temperature is even lower.

Condensation within clouds can be catalyzed by the existence of proteins produced by microbes, which function as nucleants or nucleation sites for water, and act by binding water molecules to initiate the condensation process.

Other cloud condensation nuclei are known, such as: microscopic clay fragments, salts (sodium chloride, ammonium sulfate and silver iodide) or solid pollutants such as smoke ash that cause the condensation of water around these particles.

Examples of condensation

Exhaled air

During the expiration phase, air is expelled from the lungs. This air is saturated with water vapor and also travels through the bronchi, the trachea, the larynx and the fossae where it is heated and becomes supersaturated with water vapor.

The air that goes outside, usually has a temperature higher than atmospheric and a high content of water vapor, so when it comes into contact with the surface of a mirror it experiences its condensation and is deposited on it in the form of drops of water. Water.

Air conditioning

Air conditioning is a device that compresses the refrigerant gas inside the compressor and allows it to expand by taking heat from the surrounding (ambient) air, so the air temperature decreases and when the so-called dew point is reached, the condensation thereof.

This phenomenon is manifested by the leakage of water from the air conditioner. Hence the popular idea that this is a water-producing device.

Deliquescence

It is a property of some substances to capture moisture (water) from the environment. Water is in a gaseous form and on contact with the deliquescent substance it can condense to form a liquid. An example of these substances is sodium chloride.

Distillation

It is a process that has many applications in chemistry and in industry. By using it, liquids can be separated from a mixture, based on their differences in boiling points. It can also be used for water purification, evaporating during the process.

The condensation of water vapor occurs in the condenser, which is kept cool by the circulation of water around it. In this way, the water is freed of some of the impurities that it may contain.

Cooking food

When, for example, a soup is being prepared, the water is heated with the ingredients it contains. The water evaporates and its condensation is revealed by the drops that appear on the lid of the cauldron.

Sweating from a glass of cold water

If a glass is filled with cold water, after a short time its exterior is covered with water, a product of the condensation of ambient humidity on the wall of the glass.

Fogging of bathroom mirrors

When a person takes a shower, his body is able to heat the water that runs on him and produce water vapor. When it comes into contact with the cold surface of the mirrors, it condenses, causing it to fog up.

Others

- Raindrops are a form of water condensation that takes place in clouds and then falls and irrigates the land.

- When the lens of the glasses becomes cloudy when opening a pot of boiling water.

- The drops of water that run down the outside of a glass of frozen soda on a hot day. This phenomenon happens when water vapor molecules in the air meet the surface of the glass and condense on it.

- When we can see the vapor in the air we breathe on a very cold day.

- The dew that forms on the leaves of the plants during the morning hours, thanks to the presence of hot steam in the grass that cools on the surfaces of the leaves.

- When the bathroom mirror is fogged after a shower, thanks to the effect of water vapor in the same condensate on the surface of the glass.

- By boiling water in a closed container, it is evident how the steam that reaches the lid of the container is transformed into drops thanks to the condensation process.

- Frost on the outside of a bucket of ice indicates that the evaporated water is condensing again on the outside surface of the bucket, leaving a film of ice.

- The fogging of the glass of a car thanks to the difference in temperature inside and outside it.

- During the alcohol distillation process, it goes from a gaseous to a liquid state thanks to the use of cold water along the tube through which the alcohol vapor passes.

- The water expelled by the air conditioners is water vapor that these devices collect, it condenses inside and later needs to be released.

- Condensation of the vapors of certain chemical substances in order not to lose them.

- When we perspire when wearing a diving mask or mask, the sweat vapor emitted by our body is condensed inside the mask, causing it to fog up.

- The gases used inside the lighters are condensed to be able to use them later, since they are highly volatile and would quickly dissolve in the atmosphere if they were in a gaseous state.

- Liquid nitrogen is the condensed form of a highly volatile gas usually used in the cryogenic industry.

- LPG or liquefied petroleum gas is a highly volatile gaseous substance that is stored in liquid form inside pipettes.

- The formation of a film on the windows of a house during a cold day.

- The condensation of gases to cool elements in the refrigeration industry.

- The drops of water that condense on the kitchen tiles when we open a pot with boiling water inside.

- The humidity of the environment that condenses on the skin of human beings.

- Propane gas condensed in pipettes to be used later in the kitchen.

- The interior of a Turk is full of steam and condensed water on the walls.

- Use of condensers within the food industry to alter the state of substances, such as milk.

- When you take a bottle from the refrigerator, it generates a film of condensed water vapor on the outside.

- The water cycle, where it is evident how it goes from a liquid to a gaseous state, it condenses again in the clouds and returns to irrigate the earth as rain.

- A fire extinguisher is the result of the condensation of carbon dioxide at high pressure, so that it can be stored inside a metal container.

References

1. Whitten, Davis, Peck & Stanley. (2008). Chemistry (8th ed.). CENGAGE Learning.
2. Wikipedia. (2019). Condensation. Recovered from: en.wikipedia.org
3. Jeff Fennell. (2019). What is Condensation? - Definition & Examples. Study. Recovered from: study.com
4. The Editors of Encyclopaedia Britannica. (March 28, 2019). Condensation. Encyclopædia Britannica. Recovered from: britannica.com
5. National Geographic Society. (2019). Condensation. Recovered from: nationalgeographic.org
6. Toppr. (sf). Condensation - Meaning, Process, and Examples. Recovered from: toppr.com