The States of Matter

Matter can exist in one of three states solid, liquid, or gas. A solid has both a definite shape and a definite volume. At the molecular level, the particles that make up a solid are close together and many times are locked into a very regular framework called a crystal lattice. Molecular motion exists, but it is slight. 

A liquid has a definite volume but no definite shape. It conforms to the container in which it is placed. The particles are moving much more than in the solid. There are usually clumps of particles moving relatively freely among other clumps. 

A gas has neither definite shape nor volume. It expands to fill the container in which it is placed. The particles move rapidly with respect to each other and act basically independently of each other. 

We will indicate the state of matter that a particular substance is in by a parenthetical s, 1, or g. Thus, H20(s) would represent solid water (ice), while H20(g) would represent gaseous water (steam). For a more detailed discussion of solids, liquids and gases see Chapters 8 and 12. 

Changes of State The amount of energy in a material, which determines whether it Is in the solid, liquid, or gaseous state (see Figs. 4 and 5), depends on its composition, temperature, and surrounding pressure. Different materials change from one state to another at widely different temperatures, although each substance (element or compound) does so at a 

The melting points of mixtures and solutions depend on the nature and the relative amount of each component of the solution. They are, however, lower than those of the separate components. Solder, for example, an alloy of tin and lead, melts at 183°C, a much lower temperature than either of its components tin melts at 231 °C and lead, at 328°C. 

Any two samples of a particular mineral, whatever their source or place of origin, have fhe same basic composition and characteristic crystal structure moreover, no two different minerals have identical chemical composition and crystal structure (see Textboxes 8 and 21). Quartz, for example, is a common and abundant mineral composed of silicon dioxide, a compound fhaf occurs nafurally not only as quartz but also in other crystal structures, known as polymorphs (polymorphs are minerals that have the same chemical composition but different crystal structure), some of which, listed in Table 23, have been used for a variefy of purposes. The crystal structure, which is essential for fhe characterization of solid maferials, is jusf one of a wide range of physical properties, thaf is, properties nof involving chemical differences, which provide convenient criteria for characferizing and identifying solids. 

The particles in a sample of gas move at high speeds when they are at or near room temperature. For example, the molecules found in the air in 

FIGURE 5.11 The three states of matter. The particles represented by the circles can be atoms, molecules, or ions (in liquids and solids), (a) In a gas, particles are very far apart and move rapidly in straight lines, (b) In a liquid, the particles move about at random, alone or in clusters, (c) In a solid, the particles or ions are in fixed positions and can only vibrate in place. 

Condensation and solidification temperatures for some gases at 1 atm pressure  

Condensation The change of molecules from the gaseous state to the liquid state 

Fluid A state of matter that is capable of flowing a gas or a liquid 

Water is one of the most familiar substances in our world. We recognize water in three different states solid, liquid, and gas. If we lower the temperature of liquid water, it freezes— that is, it changes to ice (solid water). On the other hand, if we heat water to its boiling point, it disappears into the air as a gas. 

The three states of water have distinctly different properties. If a pond freezes in the winter, you can walk across it. Solid water can support your weight. Conversely, you would never try to walk across the same pond in the summertime  

A gas has no fixed volume or shape. It uniformly fills any container. 

The three states of water solid (ice), liquid (water), and gas (water vapor in the air) 

Substance with a definite volume that takes the shape of its container 

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Barker J A and Henderson D 1976 What is a liquid Understanding the states of matter Rev. Mod. Phys. 48 587... 

A gas is defined as the state of matter distinguished from solid and liq uid states by very low density and viscosity, relatively great expansion and contraction with changes in pressure and temperature, and the ability to diffuse readily, distributing itself uniformly throughout any container... 

Gas The state of matter characterized by complete molecular mobility and unlimited expansion at standard temperature and pressure. 

The material that makes up the universe is known as matter. Matter is defined as any substance that occupies space and has weight. Matter exists in three states solid, liquid, and gas. Each has distinguishing characteristics. Solids have a defined volume and a definite shape. Liquids have a definite volume, but take the shape of their containing vessels. Gases have neither a definite shape nor volume. Gases not only take the shape of the containing vessel, but also expand to fill the vessel, regardless of its volume. Examples of the states of matter are iron, water, and air. 

In the last decades, Chemical Physics has attracted an ever increasing amount of interest. The variety of problems, such as those of chemical kinetics, molecular physics, molecular spectros-copy, transport processes, thermodynamics, the study of the state of matter, and the variety of experimental methods used, makes the great development of this field understandable. But the consequence of this breadth of subject matter has been the scattering of the relevant literature in a great number of publications. 

In their initial stndies, Pallant and Tinker (2004) found that after learning with the molecular dynamic models, 8th and 11th grade students were able to relate the difference in the state of matter to the motion and the arrangement of particles. They also used atomic or molecular interactions to describe or explain what they observed at the macroscopic level. Additionally, students interview responses included fewer misconceptions, and they were able to transfer their understanding of phases of matter to new contexts. Therefore, Pallant and Tinker (2004) concluded that MW and its guided exploration activities could help students develop robust mental models of the states of matter and reason about atomic and molecular interactions at the submicro level. 

Therefore, as we change the state of matter, the translational degrees of freedom in liquids become severely restrieted in relation to those of the gciseous state. And, the vibrational and rotational degrees of freedom appear to be somewhat restricted, even though many of the liquid vibrational and rotational states have been found to be quite similar to those of the gaseous state. 

It should thus be clear that as we change the state of matter, the translational degrees of freedom present in gases beeome restiieted in liquids and disappear in solids. For gaseous moleeules, both vibrational and rotational degrees of fireedom are present while those of the liquid state are modified to the point where only vibrational states ean be said to truly free states. The same eannot be said for molectiles in the solid state. In the solid. 

The state of matter within these regions needs to be determined before the balance of energy and chemistry can be understood. Extreme photon fluxes break all chemical bonds, prevent molecule formation and ionise atoms but as the density of species increases the UV and far-UV photons are absorbed and molecules begin to form. Chemical reactions are, however, slow in the gas phase due to the low temperature, and molecules condense out on the surface of dust particles, perhaps forming ice grains. Once on the surface, molecules continue to be photoprocessed by the starlight as well as by the continual bombardment of cosmic rays. 

E and B are the fundamental force vectors, while P and H are derived vectors associated with the state of matter. J is the vector current density. The Maxwell equations in terms of E and B are... 

The high-density phases of QCD at low temperatures can be realized in rotating compact stars - pulsars. Therefore, the observational data from pulsars could provide potentially important information on the state of matter at super-nuclear densities, in particular the superconducting quark matter. 

The AH is dependent upon the state of matter. The enthalpy change would be different for the formation of liquid water instead of gaseous water. 

Pay close attention to the state of matter for your reactants and products and choose the corresponding value in your tabulated enthalpies. 

An equilibrium exists between a liquid and its vapor. This is just one of several equilibria that exist between the states of matter. A phase diagram is a graph representing the relationship of all the states of matter of a substance. One type of phase diagram relates the states to temperature and pressure. This type allows us to predict which state of matter will exist at a certain temperature and pressure combination. Figure 11-1 shows a general form of a phase diagram. 

If the compound is dissolved in H20, indicated by (aq), the compound takes on the prefix hydro and the suffix ic. If the compound is not in solution, the state of matter should be shown as follows ... 

The state of matter in which a substance exists depends on the competition between the kinetic energy of the particles (proportional to temperature) and the strength of the intermolecular forces between the particles. 

Matter has three common states solid, liquid, and gas.There are also some far less common states, like plasma, where the electrons are separated from their atoms.The state of matter affects the properties of the material, like whether something flows or its density. The state doesn t affect the chemical makeup... 

In occupational health practice, the following terms describe the states of matter in which chemical atmospheres may occur ... 

Table l4-3 gives a few values that will be used in subsequent examples and problems. The symbol for standard enthalpies of formation is AH°f, where the superscript denotes standard and the subscript denotes formation. Look up both elemental sulfur and nitrogen to see that the standard enthalpies for elements are 0. Then find the pairs of values for IT2O and CCI4 (carbon tetrachloride) to learn that the enthalpy depends on the state of matter. 

All the states of matter succeed one after the other upon an immense ladder, moving from the one-dimensional world towards an infinitely-dimensional world. .. and the scala of beings (meaning the centers of consciousness inhabiting complex organisms) only really begins in the three-dimensional world. ... 

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