The matter is the substance of which is done something. For example, the material of a nail can be iron. The matter of living beings is organic matter.
When we speak of matter, we refer to something that has mass and volume, that is, it occupies a space.
Matter can have two types of properties:
- Extensive properties : Depends on the amount of matter.
- Intensive properties : (or intrinsic) They do not depend on the amount of matter, ie they remain unchanged.
There are some extensive properties that can be used as intensive. For example, volume is an extensive property. However, it can become an intensive property if it is considered as a unit value, such as the molar volume (the volume of a mole of the substance).
Examples of intensive properties
- Temperature : The amount of heat in a substance. It is measured in degrees. For example: “ This water sample has a temperature of 32 degrees Celsius .” In the example, the amount of water is not specified because the intensive properties do not change with the quantity. If the sample is two liters the temperature will be the same as if the sample is 200 cm3.
- Boiling temperature : Also called boiling point. It is the maximum temperature at which a substance can reach in liquid state . If the substance exceeds that temperature, it will be in a gaseous state. For example: the boiling temperature of the water is 100 degrees C.
- Melting point or melting point : The temperature at which a substance passes from the solid to the liquid state . In general, the melting point is equal to the freezing point (for example, for water, the melting point and the freezing point is 0 degrees). However, with some exceptions such as agar-agar. Example: the melting point of silver is 961 degrees.
- Pressure : It is a physical quantity that measures the projection of force in a perpendicular direction per unit of surface. It is measured in pascals or newtons. When measuring atmospheric pressure (the pressure exerted by the atmosphere on the earth) is measured in hectopascals (hPa) that is equal to 100 pascals. Example: the pressure today in this town is 1013 hectopascals.
- Specific volume: Although the volume is an extensive property, the specific volume is an intensive property because it is the volume occupied by a unit of mass of a material. It is the inverse magnitude to the density. It is measured in units of volume by one unit of mass. For example, cubic meters per kilogram. For example: the specific volume of water at 20 degrees is 0.001002 m3 / kg.
- Density : The magnitude of the amount of mass in a given volume. That is to say that the density of a body is the ratio between the mass of a body and the volume it occupies. For example: the density of the sunflower oil is 0.891 g / cm3.
- Color : Refers to the appearance that a substance has before the human eye. For example, the color of the wood may be orange, brown or copper.
- Taste : In chemistry you rarely work with the taste of the substances, since many of them are toxic. However, it is important to remember that it is one of the intensive properties of substances. For example: the flavor of lemon is acid .
- Compressibility : The ability of the material to decrease in volume when subjected to a certain pressure or compression.
- Concentration : Given a solution, the concentration is the ratio between the amount of solute (the substance in smaller proportion, usually a solid) and the amount of solvent (substance that dissolves). The greater the amount of solute compared to that of solvent, the solution is said to be more concentrated. The smaller the amount of solute is compared to the solvent, the solution is said to be more diluted.
- Refractive index : The ratio between the speed of light and the speed of light in the substance from which we calculate the index. That is to say, the faster the light passes through that substance, the lower the refractive index. The refractive index of the vacuum is 1, the refractive index of the air is 1,0002926, the refractive index of the diamond is 2.42.
- Surface tension : It is a property of liquids. It is the ability of some liquids to prevent increasing their surface. Surface tension is the force acting tangentially per unit length at the edge of a surface of an equilibrium liquid. To the superficial tension it is due that drops of water are formed and that the water does not extend throughout a surface. The water has a surface tension of 72.75, while other liquids have lower surface tensions, such as acetone (23.70) or ethyl alcohol (22.75).
- Elasticity : The ability of some materials to return to their original form after having suffered deformations as a result of an external force.
Examples of extensive properties
Examples of extensive properties
- Weight : It is a measure of strength. It is the gravitational force acting on an object. On the earth’s surface, the weight of an object is equal to its mass. However, the weight of the same body on the Moon will be much lower, while its mass will remain the same. It is a vector magnitude.
- Mass : Is the amount of matter in a body . To measure it is used, as with weight, the kilogram. It is a scalar magnitude.
- Volume : It is the extension of an object in three dimensions. It is a magnitude derived from the length. The most used volume units are liter and cubic centimeters (cm3). One liter is 1,000 cm3.
- Potential energy : Within a physical system, the potential energy of an object is the stored energy according to its position. For example, a brick hanging from a rope two meters high has the potential energy of its fall, in case the rope is cut. Since the potential energy depends on weight, mass and volume, it is an extensive property.
- Inertia : Inertia is the ability of an object to remain in a state of rest or movement. Every state of rest (immobility) or movement is always relative, since it depends on the point of view of the observer.
- Length : In the same way that the volume changes with the amount of matter, so does the length. It is the distance between two points, but measured in only one dimension, unlike the volume that is measured in three (length, width, depth).
- Heat capacity : The amount of heat that allows a body temperature to vary by one degree. It depends on the amount of substance since, for example, more heat is needed to heat a liter of water than half a liter of water.