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This is a great guide for teachers to use in the classroom. It incudes vocabulary, physical changes of properties, and a deeper explaining of energy.

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Chem Unit 2 lecture SVHS 14-15 key-upload.pdf

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This worksheet covers all the basis of matter and energy. It includes matching and fill in the blank questions with lots of pictures which is great for visual learners.

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Matter and energy online worksheet for 3ºEP. You can do the exercises online or download the worksheet as pdf.

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An article that helps in explaining what the solid property is. Also includes a great visual comparing the three different states of matter and their structures.

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Solid, one of the three basic states of matter, the others being liquid and gas. (Sometimes plasmas, or ionized gases, are considered a fourth state of matter.) A solid forms from liquid or gas because the energy of atoms decreases when the atoms take up a relatively ordered, three-dimensional structure.

Solids exhibit certain characteristics that distinguish them from liquids and gases. All solids have, for example, the ability to resist forces applied either perpendicular or parallel to a surface (i.e., normal or shear loads, respectively). Such properties depend on the properties of the atoms that form the solid, on the way those atoms are arranged, and on the forces between them.

Solids are generally divided into three broad classes- crystalline, noncrystalline ( amorphous), and quasicrystalline. Crystalline solids have a very high degree of order in a periodic atomic arrangement. Practically all metals and many other minerals, such as common table salt (sodium chloride), belong to this class. Noncrystalline solids are those in which atoms and molecules are not organized in a definite lattice pattern. They include glasses, plastics, and gels. Quasicrystalline solids display novel symmetries in which the atoms are arranged in quasiperiodic fashion-i.e., in patterns that do not repeat at regular intervals. They exhibit symmetries, such as fivefold symmetry, that are forbidden in ordinary crystals. Quasicrystal structures are common in alloys in which aluminum is combined with another metal, such as iron, cobalt, or nickel.

Some molecules may exist in the liquid crystal state, which is intermediate to the crystalline solid and liquid states. Liquid crystals flow like liquids yet display a certain degree of the symmetry characteristic of crystalline solids.

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Four principal types of atomic bonds are found in crystalline solids: metallic, ionic, covalent, and molecular. Metals and their alloys are characterized in the main by their high electrical and thermal conductivity, which arise from the migration of free electrons; free electrons also influence how the atoms bond. Ionic crystals are aggregates of charged ions. These salts commonly exhibit ionic conductivity, which increases with temperature. Covalent crystals are hard, frequently brittle materials such as diamond, silicon, and silicon carbide. In the simpler, monatomic types (e.g., diamond), each atom is surrounded by a number of atoms equal to its valence. Molecular crystals are substances that have relatively weak intermolecular binding, such as dry ice (solidified carbon dioxide), solid forms of the noble gases (e.g., argon, krypton, and xenon), and crystals of numerous organic compounds.

Various alloys, salts, covalent crystals, and molecular crystals that are good electrical insulators at low temperature become conductors at elevated temperatures, conductivity increasing rapidly with temperature. Materials of this type are called semiconductors. Their electrical conductivity is generally low when compared with that of such metals as copper, silver, or aluminum.

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Solid, one of the three basic states of matter, the others being liquid and gas. A solid forms from liquid or gas because the energy of atoms decreases when the atoms take up a relatively ordered, three-dimensional structure. All solids are able to resist forces applied either perpendicular or parallel to a surface.

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For the reading learners, this site goes more into detail of what a liquid is and all the different physical and chemical properties of it.

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Additional Reading

A classic survey of the liquid state by a pioneer in the field is given in J.S. Rowlinson (ed.), J.D. van der Waals: On the Continuity of the Gaseous and Liquid States (1988), with an extensive bibliography. J.N. Murrell and E.A. Boucher, Properties of Liquids and Solutions, 2nd ed. (1994), is a short introduction to the physics and chemistry of the liquid state. A general approach to the chemical thermodynamics of pure substances and solutions is given in the classic text Gilbert Newton Lewis and Merle Randall, Thermodynamics, 2nd ed., rev. by Kenneth S. Pitzer and Leo Brewer (1961). J.S. Rowlinson and F.L. Swinton, Liquids and Liquid Mixtures, 3rd ed. (1982), gives a thorough treatment of the physics of fluids and of the statistical mechanics of the equilibrium properties of simple pure liquids and liquid mixtures; the work also contains a data bibliography and is primarily for research-oriented readers.

More-specialized books include John P. O'Connell, John M. Prausnitz, and Bruce E. Poling, The Properties of Gases and Liquids, 5th ed. (2001), which focuses on the vapour-liquid transition and evaluates techniques for estimating and correlating properties of gases and liquids, as well as tabulating the properties of 600 compounds; and John M. Prausnitz, Ruediger N. Lichtenthaler, and Edmundo Gomes de Azevedo, Molecular Thermodynamics of Fluid-Phase Equilibria, 3rd ed. (1998), which is written from a chemical-engineering point of view.

Those interested in the properties of water from the physical and chemical standpoint, and in terms of biological function, will find accessible introductory descriptions in Sidney Perkowitz, "The Rarest Element," The Sciences, 39:(1): 34-38 (Jan./Feb. 1999); and Mark W. Denny, Air and Water: The Biology and Physics of Life's Media (1993).

Article Contributors

Primary Contributors

Bruce E. Poling

Professor and Chairman, Department of Chemical Engineering, University of Toledo, Ohio. Coauthor of The Properties of Gases and Liquids.

John M. Prausnitz

Professor of Chemical Engineering, University of California, Berkeley. Author of Molecular Thermodynamics of Fluid-Phase Equilibria.

John Shipley Rowlinson

Dr. Lee's Professor Emeritus of Chemistry, University of Oxford. Author of Liquids and Liquid Mixtures.

Other Contributors

Other Encyclopedia Britannica Contributors

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Additional Reading A classic survey of the liquid state by a pioneer in the field is given in J.S. Rowlinson (ed.), J.D. van der Waals: On the Continuity of the Gaseous and Liquid States (1988), with an extensive bibliography. J.N. Murrell and E.A. Boucher, Properties of Liquids and Solutions, 2nd ed.

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For the reading learners, there is a lot of take away facts of the gaseous state and it's properties. Great explanations on what to teach in a lesson.

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Gas, one of the three fundamental states of matter, with distinctly different properties from the liquid and solid states.

Structure

The remarkable feature of gases is that they appear to have no structure at all. They have neither a definite size nor shape, whereas ordinary solids have both a definite size and a definite shape, and liquids have a definite size, or volume, even though they adapt their shape to that of the container in which they are placed. Gases will completely fill any closed container; their properties depend on the volume of a container but not on its shape.

Kinetic-molecular picture

Gases nevertheless do have a structure of sorts on a molecular scale. They consist of a vast number of molecules moving chaotically in all directions and colliding with one another and with the walls of their container. Beyond this, there is no structure-the molecules are distributed essentially randomly in space, traveling in arbitrary directions at speeds that are distributed randomly about an average determined by the gas temperature. The pressure exerted by a gas is the result of the innumerable impacts of the molecules on the container walls and appears steady to human senses because so many collisions occur each second on all sections of the walls. More subtle properties such as heat conductivity, viscosity (resistance to flow), and diffusion are attributed to the molecules themselves carrying the mechanical quantities of energy, momentum, and mass, respectively. These are called transport properties, and the rate of transport is dominated by the collisions between molecules, which force their trajectories into tortuous shapes. The molecular collisions are in turn controlled by the forces between the molecules and are described by the laws of mechanics.

Thus, gases are treated as a large collection of tiny particles subject to the laws of physics. Their properties are attributed primarily to the motion of the molecules and can be explained by the kinetic theory of gases. It is not obvious that this should be the case, and for many years a static picture of gases was instead espoused, in which the pressure, for instance, was attributed to repulsive forces between essentially stationary particles pushing on the container walls. How the kinetic-molecular picture finally came to be universally accepted is a fascinating piece of scientific history and is discussed briefly below in the section Kinetic theory of gases. Any theory of gas behaviour based on this kinetic model must also be a statistical one because of the enormous numbers of particles involved. The kinetic theory of gases is now a classical part of statistical physics and is indeed a sort of miniature display case for many of the fundamental concepts and methods of science. Such important modern concepts as distribution functions, cross sections, microscopic reversibility, and time-reversal invariance have their historical roots in kinetic theory, as does the entire atomistic view of matter.

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Numerical magnitudes

When considering various physical phenomena, it is helpful for one to have some idea of the numerical magnitudes involved. In particular, there are several characteristics whose values should be known, at least within an order of magnitude (a factor of 10), in order for one to obtain a clear idea of the nature of gaseous molecules. These features include the size, average speed, and intermolecular separation at ordinary temperatures and pressures. In addition, other important considerations are how many collisions a typical molecule makes in one second under these conditions and how far such a typical molecule travels before colliding with another molecule. It has been established that molecules have sizes on the order of a few angstrom units (1 Å = 10 −8 centimetre [cm]) and that there are about 6 × 10 ²³ molecules in one mole, which is defined as the amount of a substance whose mass in grams is equal to its molecular weight (e.g., 1 mole of water, H ₂ O, is 18.0152 grams). With this knowledge, one could calculate at least some of the gas values. It is interesting to see how the answers could be estimated from simple observations and then to compare the results to the accepted values that are based on more precise measurements and theories.

Intermolecular separation and average speed

One of the easiest properties to work out is the average distance between molecules compared to their diameter; water will be used here for this purpose. Consider 1 gram of H ₂O at 100° C and atmospheric pressure, which are the normal boiling point conditions. The liquid occupies a volume of 1.04 cubic centimetres (cm ³); once converted to steam it occupies a volume of 1.67 × 10 ³ cm ³. Thus, the average volume occupied by one molecule in the gas is larger than the corresponding volume occupied in the liquid by a factor of 1.67 × 10 ³/1.04, or about 1,600. Since volume varies as the cube of distance, the ratio of the mean separation distance in the gas to that in the liquid is roughly equal to the cube root of 1,600, or about 12. If the molecules in the liquid are considered to be touching each other, the ratio of the intermolecular separation to the molecular diameter in ordinary gases is on the order of 10 under ordinary conditions. It should be noted that the actual separation and diameter cannot be determined in this way; only their ratio can be calculated.

It is also relatively simple to estimate the average speed of gas molecules. Consider a sound wave in a gas, which is just the propagation of a small pressure disturbance. If pressure is attributed to molecular impacts on a test surface, then surely a pressure disturbance cannot travel faster than the molecules themselves. In other words, the average molecular speed in a gas should be somewhat greater than the speed of sound in the gas. The speed of sound in air at ordinary temperatures is about 330 metres per second (m/s), so the molecular speed will be estimated here to be somewhat greater, say, about 5 × 10 ⁴ centimetres per second (cm/s). This value depends on the particular gas and the temperature, but it will be sufficient for the kind of estimates sought here.

Mean-free path and collision rate

The average molecular speed, along with an observed rate of the diffusion of gases, can be used to estimate the length and tortuosity of the path traveled by a typical molecule. If a bottle of ammonia is opened in a closed room, at least a few minutes pass before the ammonia can be detected at a distance of just one metre. (Ammonia, NH ₃, is a gas; the familiar bottle of "ammonia" typically seen is actually a solution of the gas in water.) Yet, if the ammonia molecules traveled directly to an observer at a speed somewhat faster than that of sound, the odour should be detectable in only a few milliseconds. The explanation for the discrepancy is that the ammonia molecules collide with many air molecules, and their paths are greatly distorted as a result. For a quantitative estimate of the diffusion time, a more controlled system must be considered, because even gentle stray air currents in a closed room greatly speed up the spreading of the ammonia. To eliminate the effect of such air currents, a closed tube-say, a glass tube one centimetre in diameter and one metre in length-can be used. A small amount of ammonia gas is released at one end, and both ends are then closed. In order to measure how long it takes for the ammonia to travel to the other end, a piece of moist red litmus paper might be used as a detector; it will turn blue when the ammonia reaches it. This process takes quite a long time-about several hours-because diffusion occurs at such a slow rate. In this case, the time will be taken to be approximately 3 hours, or roughly 10 ⁴ seconds (s). During this time interval, a typical ammonia molecule actually travels a distance of (5 × 10 ⁴ cm/s)(10 ⁴ s) = 5 × 10 ⁸ cm = 5,000 kilometres (km), roughly the distance across the United States. In other words, such a molecule travels a total distance of five million metres in order to progress a net distance of only one metre.

The solution to a basic statistical problem can be used to estimate the number of collisions such a typical diffusing molecule experienced ( N) and the average distance traveled between collisions ( l), called the mean free path. The product of N and l must equal the total distance traveled-i.e., N l = 5 × 10 ⁸ cm. This distance can be thought of as a chain 5,000 km long, made up of N links, each of length l. The statistical question then is as follows: If such a chain is randomly jumbled, how far apart will its ends be on the average? This end-to-end distance corresponds to the length of the diffusion tube (one metre). This is a venerable statistical problem that recurs in many applications. One of the more vivid ways of illustrating the concept is known as the " drunkard's walk." In this scenario a drunkard takes steps of length l but, because of inebriation, takes them in random directions. After N steps, how far will he be from his starting point? The answer is that his progress is proportional not to N but to N 1/2. For example, if the drunkard takes four steps, each of length l, he will end up at a distance of 2 l from his starting point. Gas molecules move in three dimensions, whereas the drunkard moves in two dimensions; however, the result is the same. Thus, the square root of N multiplied by the length of the mean free path equals the length of the diffusion tube: N 1/2 l = 10 ² cm. From the equations for N l and N 1/2 l, it can readily be calculated that N = 2.5 × 10 ¹³ collisions and l = 2.0 × 10⁻⁵ cm. The mean time between collisions, τ, is found by dividing the time of the diffusion experiment by the number of collisions during that time: τ = (10 ⁴)/(2.5 × 10 ¹³) = 4 × 10⁻¹⁰ seconds between collisions, corresponding to a collision frequency of 2.5 × 10 ⁹ collisions per second. It is thus understandable that gases appear to be continuous fluids on ordinary scales of time and distance.

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Gas, one of the three fundamental states of matter, with distinctly different properties from the liquid and solid states. The remarkable feature of gases is that they appear to have no structure at all. They have neither a definite size nor shape, whereas ordinary solids have both a definite size

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This game is a great way to have a class interaction time. It provides examples of different states of matter then in which you have to identify if it is a solid, liquid, or gas. The examples provided are real life examples that can help students recognize different states of property in real life.

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This worksheet allows student's creative mindsets to come into play. Students can have fun coloring/decorating their alien however they would like and then describe their creation using the different states of properties.

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Properties of Matter Project - Seesaw Activity by Ellen Crum

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In our science lessons we studied about the Properties of Matter. (A property of matter is anything you can observe about matter using your five senses. Some properties of matter are texture, color, size, hardness, and shape.) Project: 1. First, you will decorate your alien.

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A video that's one big, awesome science experiment. Explains a greater understanding of the states of matter and includes a song for students to sing a long to.

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Learn that matter comes in three main forms: solids, liquids and gases. These states of matter are all around us. Watch our fun video to learn about them!

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Brainpop videos are always such a fun way to help students learn new information. This video explains the different states of matter and reviews some common questions students may have about matter.

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A part of learning matter is also being able to properly explain a property of matter. This is a great example of how the class can work together and come up with adjectives to describe each property. Students will each have a turn to come up with a word to describe a property. An excellent, learning team-effort.

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Science - Properties of Matter anchor chart | Science education middle school, Middle school science, Middle school activities

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