How does a substance transition from a liquid state to a solid state take place?
Any change in the state of matter is associated with metamorphosis of temperature and pressure. One substance can be represented in the following aggregate states: solid, liquid, gaseous.
We note that as the transition is not observedchanges in the composition of matter. The transition of matter from the liquid state to the solid state is accompanied only by a change in the forces of the intermolecular interaction, the arrangement of the molecules. Transformation from one state to another is called a phase transition.
Melting
This process involves the transformation of a solid into a liquid. It requires an elevated temperature.
For example, you can observe in nature suchcondition of substance. Physics easily explains the melting of snowflakes under the influence of spring rays. The small ice crystals, which are part of the snow, begin to break down after heating the air to zero. Melting occurs gradually. First, ice absorbs heat energy. As the temperature changes, the ice turns completely into liquid water.
It is accompanied by a significant increase in the velocity of particle motion, thermal energy, an increase in the value of internal energy.
After the achievement of the indicator, calledmelting temperature, the structure of a solid is broken. Molecules have greater freedom, they "jump", occupying different positions. The molten substance has a greater energy reserve than in the solid state.
Curing temperature
The transition of a substance from a liquid state to a solid state occurs at a certain temperature. If heat is removed from the body, it freezes (crystallizes).
The temperature of solidification is considered one of the most important characteristics.
Crystallization
The transition of matter from liquid to solid stateposition is called crystallization. When the transfer of heat from the liquid stops, the temperature drops to a certain value. The phase transition of a substance from a liquid state to a solid in physics is called crystallization. When considering a substance that does not contain impurities, the melting temperature corresponds to the crystallization index.
Both processes proceed gradually. The crystallization process is accompanied by a decrease in the average kinetic energy of the molecules contained in the liquid. The forces of attraction, through which the particles are kept in a strict order, inherent in solids, increase. After the particles acquire an ordered arrangement, a crystal is formed.
An aggregate state is a physical formsubstance, represented in a certain range of pressures and temperatures. It is characterized by quantitative properties that are changed at selected intervals:
- the ability of a substance to change shape and volume;
- absence (presence) of long-range or short-range order.
The process of crystallization is associated with entropy, free energy, density, and other physical quantities.
In addition to liquids, solids, gaseous form, one more aggregate state is produced - plasma. It can be converted to gases in the event of an increase in temperature at a constant pressure.
The framework between the various states of matterfar from always being strict. In physics, the existence of amorphous bodies capable of retaining the structure of a liquid having a small fluidity has been confirmed. Liquid crystals have the ability to polarize electromagnetic radiation, which passes through them.
Conclusion
In order to describe the various states inphysics, apply the definition of the thermodynamic phase. Critical phenomena are called states that describe the transformation of one phase into another. Solids differ by preservation over a long time period of their average position. They will make minor fluctuations (with a minimum amplitude) near the equilibrium position. Crystals have a definite shape, which will change upon transition to the liquid state. Information on the boiling point (melting) allows physicists to use transitions from one aggregate state to another for practical purposes.
