THE 7 CHARACTERISTICS OF THE MOST IMPORTANT LIQUIDS - SCIENCE - 2025

The characteristics of liquids serve to define the molecular structure and physical properties of one of the states of matter.

The most studied are compressibility, surface tension, cohesion, adhesion, viscosity, freezing point and evaporation.

The liquid is one of the three states of aggregation of matter, the other two being solid and gaseous. There is a fourth state of matter, plasma, but it only occurs under conditions of extreme pressure and temperatures.

Solids are substances that maintain their shape with which they can be easily identified as objects. Gases are substances that are found floating in the air and are dispersed in it, but they can be trapped in containers such as bubbles and balloons.

Liquids are in the middle of solid and gaseous states. Generally, by exerting changes in temperature and / or pressure, it is possible to make a liquid pass into either of the other two states.

There are a large number of liquid substances present on our planet. These include oily fluids, organic and inorganic liquids, plastics, and metals such as mercury. If you have different types of molecules of different materials dissolved in a liquid it is called a solution, such as honey, body fluids, alcohol and physiological saline.

Main characteristics of the liquid state

1- Compressibility

The limited space between its particles makes liquids an almost incompressible substance. In other words, pressing to force a certain amount of liquid into a space that is too small for its volume is very difficult.

Many car or large truck shocks use pressurized fluids, such as oils, in sealed tubes. This helps to absorb and counteract the constant hustle that the track exerts on the wheels, seeking the least transmission of movement to the vehicle structure.

2- State changes

Exposing a liquid to high temperatures would cause it to evaporate. This critical point is called the boiling point and is different depending on the substance. The heat increases the separation between the molecules of the liquid until they separate enough to disperse as a gas.

Examples: water evaporates at 100 ° C, milk at 100.17 ° C, alcohol at 78 ° C, and mercury at 357 ° C.

In the reverse case, exposing a liquid to very low temperatures would cause it to solidify. This is called the freezing point and it will also depend on the density of each substance. Cold slows down the movement of atoms, increasing their intermolecular attraction enough to harden to a solid state.

Examples: water freezes at 0 ° C, milk between -0.513 ° C and -0.565 ° C, alcohol at -114 ° C and mercury at approximately -39 ° C.

It should be noted that lowering the temperature of a gas until it becomes a liquid is called condensation, and heating a solid substance sufficiently could be able to melt it or melt it into a liquid state. This process is called fusion. The water cycle perfectly explains all these processes of state changes.

3- Cohesion

It is the tendency of the same type of particles to attract each other. This intermolecular attraction in liquids allows them to move and flow holding together until they find a way to maximize this attractive force.

Cohesion literally means "action of sticking together." Beneath the surface of the liquid, the cohesion force between the molecules is the same in all directions. However, on the surface, the molecules only have this attractive force towards the sides and especially towards the inside of the body of the liquid.

This property is responsible for liquids to form spheres, which is the shape that has the least surface area to maximize intermolecular attraction.

Under zero-gravity conditions, the liquid would keep floating in a sphere, but when the sphere is pulled in by gravity they create the familiar drop shape in an effort to stay stuck together.

The effect of this property can be appreciated with drops on flat surfaces; its particles are not dispersed by the cohesive force. Also in closed taps with slow drips; intermolecular attraction holds them together until they become very heavy, that is, when the weight exceeds the cohesive force of the liquid it simply falls.

4- Surface tension

The cohesion force on the surface is responsible for the creation of a thin layer of particles much more attracted to each other than to the different particles around them, such as air.

The molecules of the liquid will always seek to minimize the surface area by attracting themselves towards the inside, giving the sensation of having a protective skin.

As long as this attraction is not disturbed, the surface can be incredibly strong. This surface tension allows, in the case of water, certain insects to slide and stay on the liquid without sinking.

It is possible to hold flat solid objects on liquid if one seeks to disturb the attraction of the surface molecules as little as possible. It is achieved by distributing the weight across the length and width of the object so as not to exceed the cohesion force.

The cohesion force and surface tension are different depending on the type of liquid and its density.

5- Accession

It is the force of attraction between different types of particles; as its name suggests, it literally means "adherence". In this case, it is generally present on the walls of liquid container containers and in the areas where it flows.

This property is responsible for liquids wetting solids. It occurs when the adhesion force between the molecules of the liquid and the solid is greater than the intermolecular cohesion force of the pure liquid.

6- Capillarity

The adhesion force is responsible for the rise and fall of liquids when physically interacting with a solid. This capillary action can be evidenced in the solid walls of the containers, since the liquid tends to form a curve called the meniscus.

Greater adhesion force and less cohesion force, the meniscus is concave and otherwise, the meniscus is convex. Water will always curve upwards where it contacts a wall and mercury will curve downwards; behavior that is almost unique in this material.

This property explains why many liquids rise when they interact with very narrow hollow objects such as straws or tubes. The narrower the diameter of the cylinder, the force of adhesion to its walls will cause the liquid to enter the interior of the container almost immediately, even against the force of gravity.

7- Viscosity

It is the internal force or resistance to deformation offered by a liquid when it flows freely. It mainly depends on the mass of the internal molecules and the intermolecular connection that attracts them. Slower flowing liquids are said to be more viscous than easier and faster flowing liquids.

For example, motor oil is more viscous than gasoline, honey is more viscous than water, and maple syrup is more viscous than vegetable oil.

For a liquid to flow it needs the application of a force; for example gravity. But it is possible to reduce the viscosity of substances by applying heat. The increase in temperature makes the particles move faster allowing the liquid to flow easier.

More facts about liquids

As in the particles of solids, those of liquids are subject to a permanent intermolecular attraction. However, in liquids there is more space between the molecules, this allows them to move and flow without remaining in a fixed position.

This attraction keeps the volume of the liquid constant, enough so that the molecules are held together by the action of gravity without dispersing in the air as in the case of gases, but not enough to keep it in a defined shape as in the case of gases. case of solids.

In this way, a liquid will seek to flow and slide from high levels to encompass the lowest portion of a container, thus taking the shape of the container, but without changing its volume. The surface of liquids is usually flat thanks to the gravity that presses on the molecules.

All these descriptions mentioned above are witnessed in everyday life every time test tubes, plates, cups, flasks, bottles, vases, fish tanks, tanks, wells, aquariums, pipe systems, rivers, lakes and dams are filled with water.

Fun facts about water

Water is the most common and abundant liquid on earth, and it is one of the few substances that can be found in any of the three states: the solid in the form of ice, its normal liquid state, and the gaseous in the form of vapor. Water.

• It is the non-metallic liquid with the highest cohesion force.
• It is the common liquid with the highest surface tension except for mercury.
• Most solids expand when they melt. Water expands when it freezes.
• Many solids are denser than their corresponding liquid states. Ice is less dense than water, which is why it floats.
• It is an excellent solvent. It is called the universal solvent

References

1. Mary Bagley (2014). Properties of Matter: Liquids. Live Science. Recovered from livescience.com.
2. Satya Shetty. What are the Properties of Liquid? Preserve Articles. Recovered from preservearticles.com.
3. University of waterloo. The Liquid State. CAcT HomePage. Faculty of science. Recovered from uwaterloo.ca.
4. Michael Blaber (1996). Properties of Liquids: Viscosity and Surface Tension - Intermolecular Forces. Florida State Universit - Dept of Biomedical Sciences. Recovered from mikeblaber.org.
5. Chemical Education Division Groups. Proerties of Liquids. Bodner research Web. Purdue University - College of Science. Recovered from chemed.chem.purdue.edu.
6. Liquid Basics. Andrew Rader Studios. Recovered from chem4kids.com.
7. Properties of Liquids. Department of Chemistry & Biochemistry. Florida State University, Tallahassee. Recovered from chem.fsu.edu.
8. Encyclopedia of Examples (2017). Examples of Solids, Liquids and Gaseous. Recovered from examples.co.