What are the basic physical properties of materials?

The basic physical properties of materials are still many:

Electrical properties: conductivity, resistivity.

Piezoelectric, ferroelectric, dielectric constant.

Magnetic properties: diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, ferromagnetic, permeability.

Optical properties: refractive index, birefringence index, color, absorption spectrum, emission spectrum, magneto-optical conversion, electro-optic conversion.

Mechanical properties: mass, volume, length, cross-sectional area, density, hardness, strength modulus, deformation rate.

Thermal properties: temperature, melting point, freezing point, calorific value, thermal conductivity, specific heat capacity, coefficient of thermal expansion.

The basic physical properties of materials are still many:

Electrical properties: conductivity, piezoelectricity, ferroelectricity, dielectric constant, etc.

Magnetic properties: diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, ferromagnetic, permeability, etc.

Optical properties: refractive index, birefringence index, color, absorption spectrum, emission spectrum, magneto-optical conversion, electro-optic conversion, etc.

Mechanical properties: hardness, modulus of strength, deformation rate, etc.

Thermal properties: melting point, thermal conductivity, heat capacity, coefficient of thermal expansion, etc.

Physical properties are the color, smell, state, and many more of the substance. These include whether it is easy to melt, solidify, sublimate, volatile, and some properties such as melting point, boiling point, hardness, electrical conductivity, thermal conductivity, ductility, etc. There are two definitions of physical properties, one refers to the properties of substances that do not need to undergo chemical changes; The second refers to the properties that matter exhibits without chemical reactions, which are called physical properties.

Some properties are obtained from the laboratory and calculated, such as solubility, density, etc. Neither the matter changed before or after the experiment. These properties are all physical.

such as the evaporation of water; The candle is soft, not easily soluble in water, and the paraffin wax is generally white; paper shredding, etc. The properties that can be manifested without chemical change are physical properties. The properties that are manifested by chemical changes are chemical properties.

Physical properties belong to the category of statistical physics, that is, physical properties are properties exhibited by a large number of molecules, not by a single atom or molecule.

The basic physical properties of materials are still many:

Electrical properties: conductivity, piezoelectricity, ferroelectricity, dielectric constant, etc.

Magnetic properties: diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, ferromagnetic, permeability, etc.

Optical properties: refractive index, birefringence index, color, absorption spectrum, emission spectrum, magneto-optical conversion, electro-optical conversion, etc.

Mechanical properties: hardness, modulus of strength, deformation rate, etc.

Thermal properties: melting point, thermal conductivity, heat capacity, coefficient of thermal expansion, etc.

The properties of a substance that do not need to undergo chemical changes are called physical properties, which usually include the color, state, odor, hardness, melting point, boiling point, density, etc. of the substance. When the external conditions change, the properties of the substance will also change, so the conditions should be indicated when describing the properties of the substance.

1.Mass-related properties of materials: density, apparent density, compactness, and porosity.

(1) Density:The density of a material refers to the mass of the material per unit volume in an absolutely dense state, that is, the ratio of the mass of the material to the volume of the material in an absolutely dense state. The volume of a material in the absolute dense state refers to the volume excluding the internal pores of the material, i.e., the volume of the material in its natural state minus the volume of the internal pores of the material.

(2) Apparent density:The apparent density of a material refers to the mass of a material in its natural state, that is, the ratio of the mass of the material to the volume of the material in its natural state. When calculating the apparent density, if only the internal pores of the material are included and not the moisture in the pores, it is called the dry apparent density; If it includes both the internal pores of the material and the moisture within the pores, it is called wet apparent density.

Hu Feng. (3) Compactness:The compactness of a material refers to the ratio of the volume of the material in its absolute dense state to its volume in its natural state. All materials with internal pores have a density of less than 1.

The compactness of the material reflects the enrichment of the solid material in the solid material.

(4) Porosity:The porosity of a material refers to the volume of the pores inside the material as a proportion of the volume of the material in its natural state. The porosity and compactness of a material are two different perspectives to illustrate the same property of a material.

The magnitude of the density is related to many properties such as strength, water resistance, and thermal conductivity.

2.Water-related properties of materials: refers to water absorption, moisture absorption, and water resistance.

(1) Water absorption:The water absorption of a material refers to the property of the material to absorb water in water, which can be reflected by the water absorption rate of the material. The water absorption of a material is positively correlated with its porosity.

(2) Hygroscopicity:The hygroscopicity of a material refers to the property of the material to absorb water vapor in moist air, which can be reflected by the moisture content of the material. The material absorbs moisture from moist air and diffuses moisture into dry air, eventually bringing its moisture content on par with the humidity of the surrounding air.

(3) Water resistance:The water resistance of a material refers to the property of a material that does not significantly reduce its strength under the action of saturated water. Due to all kinds of wind and sun, we should fully consider the waterproof performance, water resistance, and high humidity absorption of materials when choosing materials, so as to make the building more solid.

3.Thermal properties of materials: It is the guide to thermal properties, heat capacity and thermal insulation performance.

(1) Thermal conductivity:It is the property of conducting heat from one side of the material through the other side when there is a temperature difference between the two sides of the material, which is called the thermal conductivity of the material. Thermal conductivity is expressed as thermal conductivity.

(2) Heat capacity:The property of a specific heat material that absorbs heat when it is heated and releases heat when it cools is called the heat capacity of the material.

(3) Thermal insulation material performance:The insulation material not only prevents the indoor heat from being dissipated to the outside through the roof in winter, but also prevents the outdoor heat (high temperature) from being transmitted to the room in summer. Nowadays, indoor air conditioning is popular, and it is necessary to prevent heat dissipation in winter and cold air transmission to the outdoors in summer to reduce energy consumption, so as to improve the thermal insulation and thermal insulation performance of construction projects.

Question 1: What are the physical properties of matter? The physical properties of matter.

1. All objects are composed of molecules, and various substances have many different properties. Such as the magnetic properties of substances, the electrical conductivity of substances, the thermal conductivity of substances, the hardness, elasticity, and mass of substances.

2. Magnetism of matter: The property of an object that can attract iron, cobalt, nickel and other substances is called magnetism.

3. Substances are divided into conductors, insulators and semiconductors according to their different conductivity. Conductors are objects that conduct electricity easily, such as metal; Insulators are objects that do not conduct electricity easily, such as rubber; Objects with electrical conductivity between conductors and insulators are called semiconductors, such as silicon, germanium and other materials.

4. Substances are divided into good conductors and bad conductors of heat according to the different thermal conductivity; Conductors of heat: e.g. metals; Poor conductors of heat such as plastics, etc.

5. The hardness of the substance: the hardness of the object can cut through the surface of the object with the low hardness.

Question 2: What are the physical properties of matter in life, please give ten examples. Water evaporates, ice melts, air liquefies, metal reacts with flame color, filaments become thinner.