The 9 states of aggregation of matter

Traditionally it is thought that matter can only be found in three states: solid, liquid and gas. However, this is not true. Other states of aggregation of matter have been seen that, although rare, also seem to exist.

Next we will see the main characteristics of each of these states, who discovered the most recent and what are the processes that make an object go from one state to another.

• Related article: "The 11 types of chemical reactions"

States of matter aggregation: what are they?

In physics, the state of aggregation of matter is understood as one of the characteristic ways in which matter can be presented. Historically, the distinction between states of matter was made based on qualitative properties, such as solidity of the object, the behavior of its atoms or its temperature, the traditional classification being that of liquid, solid and gas.

However, thanks to research in physics, other states have been discovered and raised that may occur in situations that, normally, are not possible to replicate, such as extremely high or low temperatures.

Next we will see the main states of matter, both those that make up the traditional classification and those that have been discovered in laboratory conditions, in addition to explaining their physical properties and how it is possible to obtain them.

Fundamental states

Traditionally, three states of matter have been spoken of, depending on how its atoms behave at different temperatures. These states are basically three: solid, liquid and gas. However, it was subsequently incorporated into the plasma between these ground states. The most remarkable thing about the following four states is that it is possible to observe them in everyday situations, while at home.

To understand the four fundamental states of aggregation of matter, in each section let's see how H2O, that is, water, is presented in each of these states.

1. Solid

Solid state objects are presented in a defined way, that is, their shape does not normally change, it is not possible to alter it without applying a great force or changing the state of the object in question.

The atoms of these objects intertwine forming definite structures, which gives them the ability to withstand forces without deforming the body in which they are. This makes these objects hard and resistant.

H2O in solid state is ice.

Objects that are in solid state usually have the following characteristics:

• High cohesion.
• Defined shape.
• Shape memory: depending on the object, it returns to the way it was when deformed.
• They are practically incompressible.
• Resistance to fragmentation
• No fluency.

2. Liquid

If the temperature of a solid is increased, it is likely that it will end up losing its shape until its well-organized atomic structure completely disappears, becoming a liquid.

Liquids have the ability to flow because their atoms, although they continue to form organized molecules, they are not so close to each other, having more freedom of movement.

H2O in a liquid state is normal, ordinary water.

In liquid state, substances have the following characteristics:

• Less cohesion.
• They have no concrete form.
• Fluency.
• Little compressible
• In the cold they contract.
• They can present diffusion.

3. Gas

In the gaseous state, matter is made up of molecules that are not bound together, having little attractive force to each other, which makes the gases do not have a defined shape or volume.

Thanks to this, they expand completely freely, filling the container that contains them. Its density is much lower than that of liquids and solids.

The gaseous state of H2O is water vapor.

The gaseous state has the following characteristics:

• Almost zero cohesion.
• No definite shape.
• Variable volume.
• They tend to take up as much space as possible.

4. Plasma

Many people do not know this state of matter, which is curious, since it is the most common state in the universe, since it is what stars are made of.

In essence, plasma is an ionized gas, that is, the atoms that compose it have separated from their electrons, which are subatomic particles that are normally found inside atoms.

Thus, plasma is like a gas, but made up of anions and cations, which are negatively and positively charged ions, respectively. This makes plasma an excellent conductor.

In gases, being at high temperatures, the atoms move very fast. If these atoms collide with each other very violently, it causes the electrons inside them to be released. Taking this into account, it is understandable that the gases found on the surface of the Sun are constantly ionized, because there is a lot of temperature, causing them to become plasma.

Fluorescent lamps, once turned on, contain plasma inside. Also, the fire of a candle would be plasma.

Characteristics of plasmas:

• They conduct electricity.
• They are strongly influenced by magnetic fields.
• Its atoms do not make up a defined structure.
• They emit light.
• They are at high temperatures.

New states

There are not only the four states already mentioned. Under laboratory conditions, many more have been proposed and discovered.. Next we will see several states of aggregation of matter that could hardly be observed while at home, but which may have been deliberately created in scientific facilities, or have been hypothesized.

5. Bose-Einstein condensate

Originally predicted by Satyendra Nath Bose and Albert Einstein in 1927, the Bose-Einstein condensate was discovered in 1995 by physicists Eric A. Cornell, Wolfgang Ketterle, and Carl E. Wieman.

These researchers achieved cool atoms to a temperature 300 times lower than what has been achieved to date. This condensate is made up of bosons.

In this state of matter the atoms are completely still. The substance is very cold and has a high density.

• You may be interested: "The 9 postulates of Dalton's atomic theory"

6. Fermi condensate

Fermi condensate is made up of fermionic particles and looks similar to Bose-Einstein condensate, only instead of using bosons fermions are used.

This state of matter was created for the first time in 1999, although it would not be until 2003 that it could be replicated with atoms instead of just fermions, a discovery made by Deborah S. Jin.

This state of aggregation of matter, which is found at low temperatures, makes matter superfluid, that is, the substance does not have any viscosity.

7. Super solid

This state of matter is particularly strange. It consists of bringing helium- (4) atoms to very low temperatures, close to absolute zero.

The atoms are arranged in a similar way to how you would expect in a normal solid, such as ice, only here, although they would be frozen, they would not be in a totally still state.

Atoms begin to behave strangely, as if they were a solid and a fluid at the same time. It is when the laws of quantum uncertainty begin to prevail.

8. Super crystal

A supercrystal is a phase of matter that is characterized by having superfluidity and, at the same time, a solidified amorphous structure.

Unlike normal crystals, which are solid, super crystals have the ability to flow without any type of resistance and without breaking the properly crystalline structure in which their atoms.

These crystals are formed by the interaction of quantum particles at low temperatures and high densities.

9. Superfluid

The superfluid is a state of matter in which the substance does not present any type of viscosity. This differs from what would be a very fluid substance, which would be one that has a viscosity close to zero, but still has viscosity.

Superfluid is a substance that, if it were in a closed circuit, would flow endlessly without friction. It was discovered in 1937 by Piotr Kapitsa, John F. Allen and Don Misener.

State changes

State changes are processes in which one state of aggregation of matter changes to another maintaining a similarity in its chemical composition. Next we will see the different transformations that matter can present.

1. Fusion

It is the passage from a solid to a liquid state through heat. Melting point is understood as the temperature to which a solid must be exposed to melt, and it is something that varies from substance to substance. For example, the melting point of ice in water is 0 degrees Celsius.

2. Solidification

It is the passage from a liquid to a solid through the loss of temperature. The solidification point, also called freezing, is the temperature at which a liquid becomes a solid. Match the melting point of each substance.

3. Evaporation and boiling

They are the processes by which a liquid passes into a gaseous state. In the case of water, its boiling point is 100 degrees Celsius.

4. Condensation

It is the change of state of matter from a gas to a liquid. It can be understood as the opposite process to evaporation.

This is what happens to water vapor when it rains, since its temperature drops and the gas goes to the liquid state, precipitating.

5. Sublimation

It is the process that consists of the change of state of a matter that is in solid state going to gaseous state, without going through the liquid state along the way.

An example of a substance that is capable of sublimation is dry ice.

6. Reverse sublimation

It consists of a gas passes to the solid state without previously transforming into a liquid.

7. Deionization

It is the change from a plasma to a gas.

8. Ionization

It is the change from a gas to a plasma.

Bibliographic references:

• Pérez-Aguirre, G. (2007). Chemistry 1. A constructivist approach. Mexico. Pearson Education.
• Valenzuela-Calahorro, C. (1995). General chemistry. Introduction to Theoretical Chemistry. Salamanca, Spain. University of Salamanca.