The category physical properties is one of the broadest synthetic concepts, which characterizes a wide range of properties of substances, objects and phenomena, without which the cognitive activity of a person is simply unthinkable.
In the broadest sense, these properties characterize all non-chemical properties of substances, that is, those that are inherent in a substance without taking into account its interaction with other substances.
These include properties such as indicators of the melting and boiling points, heat capacity and thermal conductivity, density of the substance. Electrophysical properties include inductance, thermal conductivity, and dielectric constant. Very important are properties such as absorption, color, concentration.
The most important condition for understanding the essence of physical properties and the range of characteristics that they reflect is the fact that a substance can be chemically neutral and stable only when the structure and composition of its molecules are stable. This is important, because even being in the same state of aggregation, the physical properties of a substance can be different. These differences are predetermined by a variety of circumstances, for example, the structure of the crystal lattice, its presence in the composition of a particular solution, and others.
Without exception, all substances in nature possess physical properties that determine its role and place in natural processes. For example, the melting temperature (quite often this property is given in the directories as the solidification temperature), this is the temperature limit at which a solid crystalline body can go into a liquid state. In this definition, it is important to understand that the word “can” is the key word, that is, it means that at a given temperature, the substance can be both in a liquid state and in a solid state. But, if this temperature is slightly increased, then the substance will certainly go into a liquid state, and, accordingly, vice versa. This physical characteristic of a substance is closely related to another property - the boiling point, but these properties become identical only when it comes to pure substance.
If we consider such physical properties as electrical conductivity, electrical conductivity related to the subgroup of electrophysical, it should be said that these properties characterize the ability of the human body to pass electric current through itself. Depending on this, those bodies that conduct electric current are called conductors, and those that do not pass are called dielectrics. Based on their physical characteristics data, we can immediately conclude on chemical properties. Conductors always have free carriers of electric charge, but dielectrics may not have such. This statement allows us to conclude that physical properties are closely related to chemical properties, and they mutually determine each other.
Using physical parameters, one can describe a huge amount of substances and objects surrounding us in nature. For example, the basic physical properties of nitrogen, the substance that is the main component of the air we breathe, are such.
Nitrogen is a colorless gas that has a melting point of -210 ° C, and at a temperature of -196 ° C, nitrogen boils. Nitrogen is soluble in water, and its density is 0.0012506 g / cm3. The dielectric constant of nitrogen is 1,000528 at a temperature of 25 ° C.
Or, for example, the physical properties of ozone are characterized by such indicators. Ozone is also a colorless gas with a specific smell and taste; in a liquid state it acquires a dark blue hue, and in a solid state it turns black. The melting point of ozone is -192.7 degrees, and it boils at -111.9 ° C. Ozone is soluble in water, has a dielectric constant of 1.0019 (at 0 ° C), and its density is 0.002144 g / cm3 (at 20 ° C).