Matter intensive property

Properties are the characteristics by which we can identify samples of matter. Intensive properties, such as color and brittleness, do not depend on the size of the sample, but extensive properties, such as volume, do. Intensive properties are more important in identifying substances. We can determine whether a combination of substances is a mixmre or a compound by its properties. When we combine samples of matter, the result has more matter present than any of the original samples. When we break down a sample, each of the resulting products is composed of less matter than the starting sample. (Section 1.2)... 

Extensive and intensive properties Physical properties can be further described as being one of two types. Extensive properties are dependent upon the amount of substance present. For example, mass, which depends on the amount of substance there is, is an extensive property. Length and volume are also extensive properties. Density, on the other hand, is an example of an intensive property of matter. Intensive properties are independent of the amount of substance present. For example, density of a substance (at constant temperature and pressure) is the same no matter how much substance is present. 

The measured value of an intensive property does NOT depend on how much matter is being considered. The formula for heat capacity C is C = m Cp, where m = mass and Cp = specific heat. 

A phase is defined as a state of matter that is uniform throughout in terms of its chemical composition and physical state in other words, a phase may be considered a pure substance or a mixture of pure substances wherein intensive properties do not vary with position. Accordingly, a gaseous mixture is a single phase, and a mixture of completely miscible liquids yields a single hquid phase in contrast, a mixture of several solids remains as a system with multiple solid phases. A phase rule therefore states that, if a limited number of macroscopic properties is known, it is possible to predict additional properties. 

The thermodynamic state is therefore considered equivalent to specification of the complete set of independent intensive properties 7 1 R2, Rn. The fact that state can be specified without reference to extensive properties is a direct consequence of the macroscopic character of the thermodynamic system, for once this character is established, we can safely assume that system size does not matter except as a trivial overall scale factor. For example, it is of no thermodynamic consequence whether we choose a cup-full or a bucket-full as sample size for a thermodynamic investigation of the normal boiling-point state of water, because thermodynamic properties of the two systems are trivially related. 

Physical properties are termed either intensive or extensive. Intensive properties are independent of the quantity of material present. Density, specific volume, and compressibility factor are examples. Properties such as volume and mass are termed extensive their values are determined by the total quantity of matter present. 

The characteristics, or properties, that are used to describe matter can be classified in several ways. Physical properties are those that can be determined without changing the chemical composition of the sample, whereas chemical properties are those that do involve a chemical change in the sample. Intensive properties are those whose... 

Samples of matter can be identified by using characteristic physical properties. A substance may have a unique color, odor, melting point, or boiling point. These properties do not depend on the quantity of the substance and are called intensive properties. Density also is an intensive property and may serve as a means for identification. 

List some characteristic properties of matter that are intensive properties. 

The most important chemical thermodynamic property is the chemical potential of a substance, denoted /x.18 The chemical potential is the intensive property that is the criterion for equilibrium with respect to the transfer or transformation of matter. Each component in a soil has a chemical potential that determines the relative propensity of the component to be transferred from one phase to another, or to be transformed into an entirely different chemical compound in the soil. Just as thermal energy is transferred from regions of high temperature to regions of low temperature, so matter is transferred from phases or substances of high chemical potential to phases or substances of low chemical potential. Chemical potential is measured in units of joules per mole (J mol 1) or joules per kilogram (J kg 1). 

Density, a topic that is taught in the early weeks of a chemistry course, is introduced in Chapter 6, Polymer Solutions and Dispersions. Why not use some plastic samples for density experiments Have the students identify the plastic from its density. This will enforce the concept that density is an intensive property of matter. The discussion of viscosity can also fit into a presentation on H-bonding. The explanation of polymer viscosity is ver useful for a teacher using the Chemistry in the Community curriculum. It is an excellent reference for the experiment that has the students determining viscosity by tuning the rate of fall of a plastic bead in various organic liquids. 

In nonequilibrium systems, the intensive properties of temperature, pressure, and chemical potential are not uniform. However, they all are defined locally in an elemental volume with a sufficient number of molecules for the principles of thermodynamics to be applicable. For example, in a region A , we can define the densities of thermodynamic properties such as energy and entropy at local temperature. The energy density, the entropy density, and the amount of matter are expressed by uk(T, Nk), s T, Nk), and Nk, respectively. The total energy U, the total entropy S, and the total number of moles N of the system are determined by the following volume integrals ... 

Consider a sample containing three molecules of acetylene, C2H2, and another sample containing one molecule of benzene, CgHg. Because both samples have the same number of carbon atoms (six) and both have the same number of hydrogen atoms (six), both obviously have the same percent composition. Because percent composition is an intensive property, the two compounds have the same percent composition, no matter how many molecules are present. 

The compound contains 92.3% carbon, no matter what die size of the sample is. Percent composition is an intensive property that is, compounds have definite compositions. 

The molar mass is 17.0 g/mol, no matter what size sample of the compound is considered. Molar mass is an intensive property. 

Intensive properties matter do not depend on the amount of matter given. Intensive properties are sometimes called distinctive, or characteristic, properties. Color, odor, solubility, hardness, heat/electrical conductivity, melting/freezing point, boiling point, density, luster, ductility, malleability, etc. are all intensive properties. 

Intensive property A property that does not depend on the amount of matter. 

The properties of a phase are either intensive or extensive. An intensive property is one which is independent of the total quantity of matter in the system. Examples are density, specific gravity, and specific heat. Properties such as the mass and volume of a system are termed extensive properties since their value is determined by the quantity of matter contained in the system. 

The single-scattering albedo of an aerosol, = (Ts /(crsp + (Tap)- As the ratio of two extensive properties, it is an intensive property, independent of the concentration of particulate matter. 

When scientists speak of the composition of matter, they are referring to the kinds and amounts of components of which the matter is made. On the basis of composition alone, all matter can be classified into two broad categories substances or mixtures. You have already learned that a pure substance is a form of matter with a uniform and unchanging composition. You also know that the intensive properties of pure substances do not change, regardless of the physical state or amount of the substance. But what is the result when two or more substances are combined ... 

Intensive properties are not affected by the size of the sample. Picture a piece of pure copper. It doesn t matter how big the piece of copper is it will still have that distinctive orange-brown copper color. It will still be a good conductor of electricity. It will still have the ability to be flattened into a thin sheet. It will have a certain density for a given temperature. Color, electrical conductivity, malleability, and density are all intensive properties. 

The other group of properties are the intensive properties these are characteristic of the substance (or substances) present, and are independent of its (or their) amount. Temperature and pressure are intensive properties, and so also are refractive index, viscosity, density, surface tension, etc. It is because pressure and temperature are intensive properties, independent of the quantity of matter in the system, that they are frequently used as variables to describe the thermodynamic state of the system. It is of interest to note that an extensive property may become an intensive property by specifying unit amount of the substance concerned. Thus, mass and volume are extensive, but density and specific volume, that is, the mass per unit volume and volume per unit mass, respectively, are intensive properties of the substance or system. Similarly, heat capacity is an extensive property, but specific heat is intensive. 

Properties of matter can be further classified according to whether or not they depend on the amount of substance present. The volume and the mass of a sample depend on, and are directly proportional to, the amount of matter in that sample. Such properties, which depend on the amount of material examined, are called extensive properties. By contrast, the color and the melting point of a substance are the same for a small sample and for a large one. Properties such as these, which are independent of the amount of material examined, are called intensive properties. All chemical properties are intensive properties. 

Define the following terms, and illustrate each with a specific example (a) matter (b) energy (c) mass (d) exothermic process (e) intensive property. 

In comparing the internal energies and enthalpies of different substances as we have been doing here, it is important to compare equal numbers of moles, because energy is an extensive property of matter. However, heats of reactions are commonly expressed on a molar basis and treated as intensive properties. 

Temperature, one of the seven basic physical quantities of the International System (SI) of units, is that property which describes the thermodynamic states of a system and is a measure of that system s hotness, as expressed in terms of any of several arbitrary scales. It is an indicator of the direction in which energy will flow spontaneously when two bodies are brought into contact, that is, from the hotter body to the colder one. Temperature, unlike mass and volume, is an intensive property, that is, it is independent of the quantity of matter. 

All measurable properties of matter fall into one of two additional categories extensive properties and intensive properties. The measured value of an extensive property depends on how much matter is being considered. Mass, which is the quantity of matter in a given sample of a substance, is an extensive property. More matter means more mass. Values of the same extensive property can be added together. For example, two copper pennies will have a combined mass that is the sum of the masses of each penny, and the length of two tennis courts is the sum of the lengths of each tennis court. Volume, defined as length cubed, is another extensive property. The value of an extensive quantity depends on the amount of matter. 

The measured value of an intensive property does not depend on how much matter is being considered. Density, defined as the mass of an object divided by its volume, is an intensive property. So is temperature. Suppose that we have two beakers of water at the same temperature. If we combine them to make a single quantity of water in a larger beaker, the temperature of the larger quantity of water will be the same as it was in two separate beakers. Unlike mass, length, and volume, temperature and other intensive properties are not additive. 

The density of a sample is defined as its mass per imit volume d = m/V. To get density, we merely divide the mass by the volume. Density is an intensive property of matter (it doesn t matter how much sample is present), so density is useful to identify substances. The subject is used here to review all the material covered in Sections 2.1 though 2.3. 

An intensive property is a property of matter that is independent of the c uan-tity of the substance. Density and specific gravity are intensive properties. For example, the density of one single drop of water is exactly the same as the density of a liter of water. 

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