Gases, liquids, and solids

Solids, liquids, and gases are classified as different states of matter because each has a different way of organizing its atoms and molecules. Molecules in a solid are tightly packed, while molecules in a gas move freely. 

Particles in a solid are organized, tightly packed together, and don t move around or mix together. Because of their fixed positions, solids have their own shape. The size of the atoms or molecules that 

The atoms in a molecule of table salt (NaCl), for example, are of different sizes. The sodium (Na) atoms are smaller than the larger chlorine (Cl) atoms, so the sodium atoms become packed in between the larger chlorine atoms. The resulting shape is a crystal, building-block structure. The atoms are as tightly packed as possible, but there is still a lot of space inside the crystal structure because of the difference in size of the atoms involved. 

Solids made up of only one element, by contrast, have atoms of equal size. All hydrogen atoms, for example, are the same size. This results in what chemists call a close-packed structure, where each atom is located as close to the next atom as possible. Not much space is wasted because the equal-sized atoms fit snugly together. The atoms in metals, for example, are often arranged in close-packed structures. 

There are two types of solids amorphous solids and crystalline solids. 

It is easy to tell the difference between a solid, a liquid and a gas  

A liquid flows easily. It has a definite volume but no definite shape. Its shape depends on the container. 

Water can be a solid (ice), a liquid (water) and a gas (water vapour or steam). Its state can be dianged by heating or cooling  

1 Ice slowly changes to water, when it is put in a warm place. This change is called melting. The thermometer shows 0 C until all the ice has melted, so 0 is called its melting point. 

2 When the water is heated its temperature rises, and some of it changes to water vapotu . This change is called evaporation. The hotter the water gets, the more quickly it evaporates. 

Materials may exist as solids, liquids, or gases. A specimen of solid, such as a piece of ice, has a definite volume and also has rigidity. It retains its shape even when acted on by an outside force, provided that the force is not great enough to break the specimen. A liquid, such as a portion of water in a cup, has a definite volume, but adjusts its shape to the shape of the bottom part of its container. A gas, such as steam (water vapor) in the cylinder of a steam engine, has neither definite shape nor definite volume — it changes its shape and also its volume with change in the shape and volume of the container. 

and water vapor represent the same chemical substance, water substance, in three different states. Ice is the solid state (crystalline state), water the liquid state, and water vapor the gaseous state. 

Scientists usually distinguish between crystalline solids and noncrystalline solids, 

A crystal is a homogeneous material (either a pure substance or a solution) that, as a result of its regular internal structure, has spontaneously assumed the shape of a figure bounded by plane faces.  

For example, when a solution of salt evaporates, small cubes of solid salt form. These cubes, which are bounded by plane square faces, are crystals. 

Matter exists on earth in three physical states solids, liquids, and gases. In the solid state H2O is known as ice, in the liquid state it is called water, and in the gaseous state it is known as steam or water vapor. Most, but not all, substances can exist in all three states. Most solids change to liquids and most liquids turn into gases as they are heated. Liquids and gases are known as fluids because they flow freely. Solids and liquids are referred to as condensed states because they have much higher densities than gases.Table 12-1 displays the densities of a few common substances in different ph)rsical states. 

As the data in Table 12-1 indicate, solids and liquids are many times denser than gases. The molecules must be very far apart in gases and much closer together in liquids and solids. For example, the volume of one mole of liquid water is about 18 milliliters, whereas one mole of steam occupies about 30,600 milliliters at 100°C and atmospheric pressure. Gases are easily compressed, and they completely fill any container in which they are present. This tells us that the molecules in a gas are far apart relative to their sizes and that interactions among them are weak. Because they are so far apart, gaseous molecules would not interact with one another were it not for their rapid motion and frequent collisions. 

All gases can be liquefied by cooling and compressing them. Volatile liquids easily evaporate to form gases at room temperature or slightly above. The term vapor refers to a gas that is formed by evaporation of a liquid or sublimation of a solid. We often use this term when some of the liquid or solid remains in contact with the gas. 

Many important chemical substances are gases at ambient conditions. The earth s atmosphere is a mixture of gases and particles of liquids and solids (Table 12-2). The major gaseous components are N2 (bp = - 195.79°C) and O2 (bp = — 182.98°C), with smaller concentrations of other gases. All gases are miscible-, that is, they mix completely unless they react with one another. 

Several scientists, notably Torricelli (1643), Boyle (1660), Charles (1787), and Graham (1831), laid an experimental foundation on which our present understanding of gases is based. Their investigations showed that 

Intermolecular forces are responsible for the condensed states of matter. The particles making up solids and liquids are held together by intermolecular forces, and these forces affect a number of the physical properties of matter in these two states. Intermolecular forces are quite a bit weaker than the covalent and ionic bonds discussed in Chapter 7. The latter requires several hundred to several thousand kilojoules per mole to break. The strength of intermolecular forces are a few to tens of kilojoules per 

States of elements under normal conditions. Light gray indicates gas, dark gray indicates liquids, all the rest are solids. 

Solid strong incompressible definite shape high definite 

Liquid strong nearly incompressible assumes that of container high definite 

Gas practically zero compressible fills container low assumes volume of container 

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Numerous types of equations of state apply to solids, liquids, and gases a few of these are considered here. 

Auxiliary fuel firing Combustion of an auxiliary fuel to provide additional heat to an incinerator in order to either dry or Ignite the waste material and to maintain ignition, to ensure complete combustion of solids, liquids, and gases in the incinerator. 

This subsection deals with the handling, storage, and transportation of solids, liquids, and gases. Each form is considered individually. 

Conduction is the process by which heat flows by molecular transportation along or through a material or from one material to another, the material receiving the heat being in contact with that from which it receives it. Conduction takes place in solids, liquids and gases and from one to another. The rate at which conduction occurs varies considerably according to the substance and its state. 

The old classification of bodies into solids, liquids, and gases, based on differences in viscosity and elasticity, is not altogether satisfactory. We shall therefore adopt a method in which bodies are divided into two classes according to the nature of their... 

Multiphase systems containing solids, liquids and gases. 

Multiphase systems, solids, liquids and gases 181 Multiple stage pumps, vacuum producing 365 Multistage compression 353 ----number of stages 354... 

Soil is a multi-phase system consisting of solids, liquids, and gases. In a typical soil, solids, liquids and gases compose about 50%, 20-30% and 20-30% respectively of the total soil volume (Brady and Weil, 1999). The solid phase can be broken down into two components inorganic and organic matter, with organic matter ranging from 1 to 5% of the soil. 

The role of plastics in municipal solid waste combustion is discussed, and in particular, their fuel characteristics. Details are given of a state-of-art municipal solid waste combustor and the effects of plastics on the different combustion stages. In addition, the contribution of plastics to the total output spread over the various emission paths of solids, liquids and gases, is also assessed. 

The principles of stoichiometiy apply equally to solids, liquids, and gases. That is, no matter what phase substances are in, their chemical behavior can be described in molecular terms, and their transformations must be visualized and balanced using molecules and moles. 

Nearly every substance that dissolves in water has an upper limit to its solubility. Solids, liquids, and gases all display this characteristic. The room-temperature solubility of solid NaCl in water is about 6 M. Liquid n-hexanol forms a saturated aqueous solution at a concentration of 5.6 X 10 M. Gaseous O2 in the Earth s atmosphere... 

The purpose of this compilation is to tabulate the densities of compounds, hence only minimal description of experimental methods used to measure the density of liquids or solids appears. Detailed descriptions of methods for density determination of solids, liquids and gases, along with appropriate density reference standards, appear in a chapter by Davis and Koch in Physical Methods of Chemistry, Volume VI, Determination of Thermodynamic Properties [86-ros/bae],... 

The analysis is applicable to all elements except hydrogen in solids, liquids and gases, although it is normally confined to the study of solids in the form of powder or plates. 

This paper is a review of methods for estimating releases of chemicals into the environment in the course of extraction of raw materials, manufacturing, use, storage, transportation, and disposal, as well as by accidents or natural processes. It discusses source types, forms of substances released (solids, liquids, and gases), receiving media (air, water, soil), time pattern of release (continuous versus intermittent, cyclic versus random), and geographic patterns of release (point, line, area, and volume sources). 

Phase—Solids, liquids, and gases (at ambient conditions) are represented. 

H. Ledbetter and S. Kim, Monocrystal Elastic Constants and Derived Properties of the Cubic and Hexagonal Elements, in Handbook of Elastic Properties of Solids, Liquids and Gases. 2, 97 (2001). 

The absolute value of the entropy of a compound is obtained directly by integration of the heat capacity from 0 K. The main contributions to the heat capacity and thus to the entropy are discussed in this chapter. Microscopic descriptions of the heat capacity of solids, liquids and gases range from simple classical approaches to complex lattice dynamical treatments. The relatively simple models that have been around for some time will be described in some detail. These models are, because of their simplicity, very useful for estimating heat capacities and for relating the heat capacity to the physical and chemical... 

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. 

Drugs can be beneficially used in therapy as solids, liquids, and gases. The form most commonly used in drug therapy is solid, followed by liquid and then gas. Liquid drugs can pose an interesting challenge in dosage-form development since many of the liquids are volatile substances and, as such, must be physically sealed from the atmosphere to prevent their loss. 

PL. Smith, A primer for sampling solids, liquids and gases - Based on the seven sampling errors of Pierre Gy, ASA SIAM, Philadelphia, 2001. 

Analytically, IR (FTIR) spectroscopy is unquestionably one of the most versatile techniques available for the measurement of molecular species in the laboratory today, and also for applications beyond the laboratory. A major benefit of the technique is that it may be used to study materials in almost any form, and usually without any modification all three physical states are addressed solids, liquids and gases. Also, it is a fundamental molecular property, and as such the information content can be considered to be absolute in terms of information content, and as such can be very diagnostic in terms of material purity and composition. Traces of impurities can be both uniquely detected and in most cases characterized. This is a very important attribute in a process analytical enviromnent. 

Electron impact (El) ionization is one of the most classic ionization techniques used in mass spectrometry. A glowing filament produces electrons, which are then accelerated to an energy of 70 eV. The sample is vaporized into the vacuum where gas phase molecules are bombarded with electrons. One or more electrons are removed from the molecules to form odd electron ions (M+ ) or multiply charged ions. Solids, liquids and gases can be analyzed by El, if they endure vaporization without decomposition. Therefore the range of compounds which can be analyzed by El is somewhat limited to thermally stable and volatile compounds. The coupling with gas chromatography has been well established for... 

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