The melting point is the temperature at which a solid substance turns into a liquid state.
The temperature at which a matter that is in a solid state changes to its liquid state is known as the melting point . For the change of state to occur, said temperature must be constant .
The melting point is an intensive physical property of matter; This means that it is not linked to the amount of substance or the size of the body. In the fusion process, the solid matter begins to heat up until it reaches the melting point, at which point its change of state occurs and it transforms into a liquid.
If the liquid continues to heat, it can reach its boiling point : from this temperature, a new change of state occurs, this time going from liquid to gaseous. It should be noted that, while the boiling point is directly related to pressure, the melting point has little link with said factor.
Melting point temperature
When it is a pure substance , the fusion process takes place at a single temperature. In this way, the addition of heat will not be reflected in an increase in temperature until the fusion process is complete and the matter has already become a liquid.
Let's see what the case of water is like. The melting point of H2O is 0 degrees . In this way, when water is at a lower temperature, it is in a solid state. Between 0 and 99 degrees , it is in a liquid state. Because its boiling point is 100 degrees , at that temperature it passes into the gaseous state.
The melting point of water is 0 ºC.
Diffusion process
As with many other concepts in science, it is important to point out some of their real-world applications, since while they have become part of fundamental theory , their discovery took place through experimentation and observation. Let's see, next, the bases of the concept of the diffusion process .
Initially, the term diffusion gave the idea of self-mixing , a process that takes place in the molecules of a fluid due to their thermal movement. Although molecular diffusion (explained later) is based on this principle, currently diffusion is also understood as self-mixing processes that are not induced by thermal movement, such as those that use agents external to the fluid, which They force homogenization by providing energy (this is the basis of turbulent diffusion ).
The self-mixing process known as molecular diffusion takes advantage of the concept of melting point and occurs due to the thermal movement of the molecules of a fluid. It is important to note that the word "molecules", in this case, does not always refer to the set of atoms itself, but can also speak of small portions of the fluid in question if, for example, the element to which it is applied is the water.
In its industrial use, turbulent diffusion offers much greater effectiveness than molecular diffusion, and this can be seen in its values and in the presence of properties that are not found in the latter.
Other applications of the melting point
Another application of the melting point is metal alloys, since this temperature must be reached for handling and molding; and the manufacture and construction of various commonly used products such as windows, bars, safes and warehouses.
The determination of the purity of an acid to ensure that its use will not bring negative consequences and the identification of unknown substances, through the comparison of the results with those of common substances, are other actions that resort to the knowledge of the point of fusion.