Three States of Matter

TABLE 4.2. Characteristics of Protons, Electrons, and Neutrons in Terms of Charge, Charge Number, and Mass 

Matter can be classified according to its physical state. The three principal states of matter inclnde the soUd, liquid, and gaseous phases, in decreasing levels of stmctnre and atonuc order. 

Liquids have a definite volnme but will take the shape of the container into which they are placed. There is a more random arrangement of particles in liquids. You can pour milk in a glass, in a cnp, or in a bowl. Milk is a liquid and it takes the shape of its container. Water, snch as that found in a lake or a river, or the water that we drink, is also a liquid. 

Gases are the least structured of the phases. A gas will take the shape and volume of the container in which it is placed. Particles in a gas are highly disordered and are relatively far apart. In gases, atoms are moving around randomly and do not occupy any specific position in space. 

The physical properties of the material depend on the phase of the material. When undergoing a phase change, the substance remains chemically identical, but its appearance (the way it appears to the naked eye) is different. The physical state, size, or shape may have changed but there is no creation of a new substance in a physical change. The identity of the substance is preserved. Important physical properties in engineering and chemistry include density, thermal conductivity (the ability of a substance to transfer heat energy), and specific heat (the ability of the substance to retain energy). 

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FIGURE A.l A molecular representation of the three states of matter. In each case, the spheres represent particles that may be atoms, molecules, or ions, (a) In a solid, the particles are packed tightly together, but continue to oscillate, (b) In a liquid, the particles are in contact, but have enough energy to move past one another, (c) In a gas, the particles are far apart, move almost completely freely, and are in ceaseless random motion. 

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. 

The next concept which we wish to examine is that of the differences between the three states of matter, gases, liquids and solids. In this case, we will find very significant differences in their energy content, namely that the gaseous form is the most energetic while the solid has the least energy. 

Liquid water is difficult to find in the universe. Scientists have found frozen ice in places such as Mars and gaseous water vapor in atmospheres such as that on Venus. However, no one has been able to find liquid water anywhere other than on Earth. Water is the only natural substance that is found in all three states of matter (solid, liquid, and gas) at the temperatures normally found on Earth. By exploring a few of the properties of water, you will discover what makes water unique. 

Note that the diagram has three general areas corresponding to the three states of matter solid, liquid, and gas. The line from A to C represents the change in vapor pressure of the solid with temperature for the sublimation (going directly from a solid to a gas without first becoming a liquid) equilibrium. The A to... 

D line represents the variation in the melting point with pressure. The A to B line represents the variation of the vapor pressure of a liquid with pressure. This B point shown on this phase diagram is the critical point of the substance, the point beyond which the gas and liquid phases are indistinguishable from each other. At or beyond this critical point, no matter how much pressure is applied, it is not possible to condense the gas into a liquid. Point A is the triple point of the substance, the combination of temperature and pressure at which all three states of matter can exist. 

In flotation, all three states of matter - solid, liquid, gas - are involved and each of these involves surface chemistry. Among the various process steps that are involved are ... 

Summary Of the three states of matter—gases, liquids, and solids—gases are probably the best understood and have the best descriptive model. 

The triple point is the combination of temperature and pressure on a phase diagram where all three states of matter exist in equilibrium. 

Gases are one of the three states of matter, along with solids and liquids. They re much less structured than the other two gases easily change both their volume and shape. A gas will not only flow like a liquid, it will also expand to fill a container. 

Learning the characteristics of the three states of matter solid, liquid, and gas... 

Nearly every substance can exist as a solid, a liquid, or a gas. These are the three common states of matter. Whether a substance is a solid or a liquid or a gas depends on its temperature and the pressure placed on it. At room temperature (about 22° C) and at the normal pressure exerted by the atmosphere, water exists as a liquid, which can flow from one container to another. But if its temperature is lowered to about —10° C, liquid water freezes to solid ice. Going the opposite direction in temperature and at this same pressure, water changes to a gas when the temperature exceeds 100° C. Changes in state can also occur by changing the pressure while holding temperature constant. The relationship between temperature and pressure and the three states of matter is easier to see when displayed in a phase diagram. Because phase diagrams provide so much information, they are known for thousands of substances. 

The aim of this book is to introduce to the principles and applications of a branch of chemistry called surface and colloid chemistry. Most science students are taught physicochemical principles pertaining to gases, liquids, and solids. The matter around us is recognized to be made of these three states of matter. However, in university chemistry textbooks, seldom more than a chapter is devoted to the science of surface and colloid chemistry. At technical schools worldwide, the same is the case, in general. However, in the realm of applications of physico-chemical technology, the science of surface and colloid chemistry is one of the most important. Common examples of the principles at work in this field are ... 

The macroscopic properties of the three states of matter can be modeled as ensembles of molecules, and their interactions are described by intermolecular potentials or force fields. These theories lead to the understanding of properties such as the thermodynamic and transport properties, vapor pressure, and critical constants. The ideal gas is characterized by a group of molecules that are hard spheres far apart, and they exert forces on each other only during brief periods of collisions. The real gases experience intermolecular forces, such as the van der Waals forces, so that molecules exert forces on each other even when they are not in collision. The liquids and solids are characterized by molecules that are constantly in contact and exerting forces on each other. 

Although atoms are not mentioned in the brief prospectus, chemical atomism is the basis of Daltons New System, in which the third chapter clearly tends to place the whole science of Chemistry upon a new, and more simple basis. It is interesting that the new atomic chemistry does not occur in Daltons book until the third chapter, which occupies less than ten percent of Part I. Chapter One is chiefly focused on heat and gases, and Chapter Two on the three states of matter. As we have already seen, the third chapter presents his method for determining the relative weights of the atoms, with the promise that from... 

Chemistry is about what matter is like and how it behaves, and our explanations and predictions of its behaviour. What is matter This word is used to cover all the substances and materials from which the physical universe is composed. There are many millions of different substances known, and all of them can be categorised as solids, liquids or gases (Figure 1.1). These are what we call the three states of matter. 

The kinetic theory can be used as a scientific model to explain how the arrangement of particles relates to the properties of the three states of matter. 

Solids, liquids and gases The three states of matter to which all substances belong. 

The following diagram shows the three states of matter and how they can be interchanged. 

First, the classical three states of matter and the transition from one state to another will be critically discussed. Second, case studies will be presented for a subsequent comparison with similar phenomena in the Leld of powdertechnology. 

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