Matter homogeneous mixtures

A solution is a homogeneous mixture of two or more substances. As described in Chapter 3, a solution contains a solvent and one or more solutes. The solvent determines the state of the solution, and normally the solvent is the component present in the greatest quantity. The most common solutions are liquids with water as solvent, but solutions exist in all three states of matter. The atmosphere of our planet, air, is a gaseous solution with molecular nitrogen as the solvent. Steel is a solid solution containing solutes such as chromium and carbon that add strength to the solvent, iron. 

Sigma (a) bonds Sigma bonds have the orbital overlap on a line drawn between the two nuclei, simple cubic unit cell The simple cubic unit cell has particles located at the corners of a simple cube, single displacement (replacement) reactions Single displacement reactions are reactions in which atoms of an element replace the atoms of another element in a compound, solid A solid is a state of matter that has both a definite shape and a definite volume, solubility product constant (/ p) The solubility product constant is the equilibrium constant associated with sparingly soluble salts and is the product of the ionic concentrations, each one raised to the power of the coefficient in the balanced chemical equation, solute The solute is the component of the solution that is there in smallest amount, solution A solution is defined as a homogeneous mixture composed of solvent and one or more solutes. 

SN1 and reactions Two varieties of nucleophilic substitution, with unimolecular and bimolecular ratedetermining stages, respectively, sol A colloidal dispersion of solid particles in a liquid, solid A rigid form of matter that maintains the same shape whatever the shape of its container, solid emulsion A colloidal dispersion of a liquid in a solid. Example butter, an emulsion of water in butterfat. solid solution A solid homogeneous mixture of two or more substances. 

Solutions are homogeneous mixtures that contain particles the size of a typical ion or small molecule. Any one state of matter can mix with any other state, leading to seven possible kinds of solutions. For solutions in which a gas or solid is dissolved in a liquid, the dissolved substance is called the solute and the liquid is called the solvent. 

A solution is a homogeneous mixture of a solute and solvent. In a classification of matter, matter is divided into mixtures and pure substances. Mixtures are divided into homogenous mixtures, solutions, and heterogeneous mixtures such as suspensions. Pure substances are divided into elements made up of atoms and compounds made up of molecules. 

The word "matter" describes everything that has physical existence, i.e. has mass and takes up space. However, the make up of matter allows it to be separated into categories. The two main classes of matter are pure substance and mixture. Each of these classes can also be divided into smaller categories such as element, compound, homogeneous mixture or heterogeneous mixture based on composition. 

Some mixtures have special characteristics. A mixture that is uniform throughout, with no phase boundaries, is called a homogeneous mixture. If you were to sample any part of the system, the same components in the same proportions would be found in each sample. The most familiar of these homogeneous mixtures is the liquid solution here a solute (either a solid or a liquid) is thoroughly and uniformly dispersed into a solvent (a liquid). If the solution were allowed to remain standing, the components would not separate, no matter how much time was allowed to pass. 

Mineral matter was a Deis ter table concentrate from Robena mine coal. It contained 68% pyrite and less than 4% organic material. The remainder was largely clay. In one case, a handpicked sample taken from a pyrite nodule found in a Pittsburgh seam coal was used. The microcrystals were crushed and sieved to 325 x 400 mesh. X-ray diffraction analysis indicated the only major component was pyrite, with a trace of marcasite also present. After heating in tetralin at 450°C for 15 min., the X-ray diffraction patterns of the recovered microcrystals indicated conversion was complete to pyrrhotite 1C. The coal was hvB, Homestead Mine, Kentucky, ground to pass 200 mesh. Ash and pyrite contents were 16.8% and 4.9%, respectively. The asphaltene was a homogenized mixture of samples isolated from liquid products derived from Pittsburgh seam, hvA coal. Its ash content was <0.1%( ). 

Figures 2 and 3 contain yield curves for naphthalene and 1-methylindan as a function of reaction time for tetralin and tetralin plus coal, pyrite, or asphaltene. The asphaltene was a homogenized mixture of several samples isolated from coal liquefaction products during other work in our laboratory (9). This asphaltene sample contained essentially a negligible ash content (<0.1%). Therefore, it contains many organic structures similiar to those found in coal, but unlike coal, its reactions will be free of any complicating factors due to mineral matter. The yields of naphthalene and 1-methylindan are greater in the presence of asphaltene than in its absence, although not quite as high as in the presence of coal. This is additional evidence that these two products arise mainly from reactions associated with the presence of the organic portion of coaly matter. These reactions are quite likely free radical in nature.

Two or more substances—elements, compounds, or both—can combine physically to produce a mixture. A mixture can be separated into its components by physical means. Mixtures are physical combinations of substances that have properties related to those of their components but that do not have definite compositions. They can be either heten eneons or homc eneons mixtures. In heterogeneous mixtures, two or more different types of matter can be seen to be present with the naked eye or a good optical microscope. Homogeneous mixtures, also called solutions, look alike throughout, even under a microscope. 

The sugar forms a solution—a homogeneous mixture—with the water. The mud and water form a heterogeneous mixture. Particles of mud are easy to see in the mud-water mixture, but seeing any sugar particles in the sugar-water solution is impossible, no matter how hard we look (even with a microscope). 

Matter includes every material thing in the universe. To be able to understand such a wide variety of items, we must classify matter. Matter is divided into pure substances and mixtures. Pure substances may be elements or compounds. Mixtures may be either heterogeneous or homogeneous. Elements are the fundamental building blocks of matter and cannot be broken down to simpler substances by chemical or physical means. Compounds are chemical combinations of elements they have their own sets of properties and have definite compositions. A physical combination of substances results in a mixture, whose components retain most of their properties. Mixtures do not have definite compositions. Homogeneous mixtures, called solutions, look alike throughout, but some parts of a heterogeneous mixture can be seen to be different from other parts. (Section 1.1)... 

From the purely thermo-dynamic point of view one might be inclined to content oneself with the empirical composition of such a homogeneous mixture, since under given circumstances, e. g. of temperature and pressure, only one definite arrangement of matter is in equilibrium, and that is given by the quantitative composition. Still, as will be seen below, by working from molecular and atomistic conceptions, it is possible to develop laws, verified by experiment, which... 

As you learned in Chapter 3, most of the forms of matter that you encounter are mixtures. A mixture is a combination of two or more substances that keep their basic identity. Components of a mixture come in contact with each other but do not undergo chemical change. You have been studying homogeneous mixtures called solutions so far in this chapter. Not all mixtures are solutions, however. Heterogeneous mixtures contain substances that exist in distinct phases. Two types of heterogeneous mixtures are suspensions and colloids. 

Recognize various forms of matter homogeneous and heterogeneous mixtures, substances, compounds, and elements... 

Everyday Materials Matter may be subdivided into elements, compounds, and heterogeneous and homogeneous mixtures. Describe one material found in a household that belongs in each category. 

Schematic representation of some classes of matter. A pure substance (a) consists of a single component. A homogeneous mixture (b) has a uniform distribution of components. A heterogeneous mixture (c) has a nonuniform distribution of components.

Somewhere between the sizes of an atom and a grain of sand lies the realm of small particles called colloids. As will become evident, they are everywhere. The simplest colloidal materials, also generally known as suspensions or dispersions, consist of two mixed phases. The continuous or dispersing phase may be gas, liquid, or solid (or even plasma, the fourth phase of matter). Air, water, and plastics are common examples. The colloid particles make up the dispersed or suspended phase when uniformly distributed in the second, continuous phase. The dispersed matter may also be gas, liquid, or solid, and any combination in more complex suspensions. Colloidal dispersions are considered homogeneous mixtures even though they can be heterogeneous at or below the microscale. 

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