Transition modern society to the information age of its development puts forward as one of the main tasks facing school education, the task of forming the foundations of the information culture of the future specialist. The implementation of this task is impossible without the inclusion of an information component in the system of chemical education.
IN modern conditions it is necessary to prepare students for the rapid perception of information and the successful display and use of it. Computer on modern lesson does not replace obsolete tables, but should become an "active" participant in the learning process, and most importantly, the learning process. Educational presentations should be created not only as illustrative material, their use in teaching chemistry is most natural for modeling chemical phenomena and processes that are almost impossible to show in a lesson.
Presentations such as "Solids: amorphous and crystalline state" increase the motivation for learning in the classroom, help to increase the level of individualization of learning and the possibility of organizing operational control over the assimilation of knowledge. This presentation is effectively used to form the basic concepts necessary for understanding the microworld, such as the most important concepts like chemical bond, crystal lattices, crystal lattice node. The presentation simulated such properties as brittleness, electrical conductivity, ductility.
The presentation "Solids: amorphous and crystalline state" can be used when studying this topic in grade 8, and in classes with different levels preparation: illustratively in weak classes, in strong classes, students can organize comments after independent study of the material, to generalize the acquired knowledge. The structure of the presentation allows you to use its individual slides in the study of specific substances - metals, non-metals. This presentation can be widely used in general lessons in grade 11.
To track the level of assimilation of the material in the presentation, tables have been compiled to fill in, moreover, the student can work independently, in stages and receive a hint if necessary. Final test brings the student to the final result and allows you to evaluate his work.
Further work is provided for students who are interested in this topic. The section "Beyond the pages of the textbook" gives direction in the future self-study Topics. I use this presentation not only in the lessons, but also when passing elective course"Minerals and Gems".
Ionic crystal cell ions at the lattice sites. The chemical bond is ionic. Properties of substances: 1) relatively high hardness, strength, 2) brittleness, 3) heat resistance, 4) refractoriness, 5) non-volatility Examples: salts (NaCl, K 2 CO 3), bases (Ca (OH) 2, NaOH)
Atomic crystal lattice At the lattice nodes are atoms. The chemical bond is covalent non-polar. Properties of substances: 1) very high hardness, strength, 2) very high Tm (diamond 3500 ° C), 3) refractoriness, 4) practically insoluble, 5) non-volatility Examples: simple substances (diamond, graphite, boron, etc.), complex substances (Al 2 O 3, SiO 2) diamond graphite
Molecular crystal lattice At the lattice sites of a molecule. The chemical bond is covalent polar and non-polar. Properties of substances: 1) low hardness, strength, 2) low Tm, Tbp, 3) at room temperature, usually liquid or gas, 4) high volatility. Examples: simple substances (H 2, N 2, O 2, F 2, P 4, S 8, Ne, He), complex substances (CO 2, H 2 O, sugar C 12 H 22 O 11, etc.) iodine I 2 carbon dioxide CO 2
The law of constancy of composition (Proust) Molecular chemical compounds, regardless of the method of their preparation, have a constant composition and properties.
10th grade students "A" high school№1997 Khachatryan Knarik Check: Pankina L.V. Physics Subject: Amorphous bodies
Amorphous bodies Amorphous bodies are bodies that, when heated, gradually soften, become more and more fluid. For such bodies it is impossible to specify the temperature at which they turn into a liquid (melt)
Crystalline bodies Crystalline bodies are bodies that do not soften, but turn from a solid state immediately into a liquid. During the melting of such bodies, it is always possible to separate the liquid from the still unmelted (solid) parts of the body.
Examples Amorphous substances include glass (artificial and volcanic), natural and artificial resins, adhesives, and other rosin, sugar candy, and many other bodies. All these substances become cloudy over time (glass “devitrifies”, candy “candied”, etc.). This turbidity is associated with the appearance inside the glass or candy of small crystals, the optical properties of which are different from those of the surrounding amorphous medium.
Properties Amorphous bodies do not have a crystalline structure and, unlike crystals, do not split with the formation of crystalline faces; as a rule, they are isotropic, that is, they do not exhibit different properties in different directions, and do not have a definite melting point.
Amorphous bodies, how they differ from crystals Amorphous bodies do not have a strict order in the arrangement of atoms. Only the nearest atoms-neighbors are arranged in some order. But there is no strict repetition in all directions of the same structural element, which is characteristic of crystals, in amorphous bodies. According to the arrangement of atoms and their behavior, amorphous bodies are similar to liquids. Often the same substance can be in both a crystalline and an amorphous state. For example, quartz SiO2 can be in both crystalline and amorphous form (silica).
liquid crystals. In nature, there are substances that simultaneously have the basic properties of a crystal and a liquid, namely anisotropy and fluidity. This state of matter is called liquid crystal. Liquid crystals are mostly organic matter, whose molecules have a long filamentous shape or the shape of flat plates. Soap bubbles are a prime example of liquid crystals.
liquid crystals. Refraction and reflection of light occur at the domain boundary, so liquid crystals are opaque. However, in a liquid crystal layer placed between two thin plates, the distance between which is 0.01-0.1 mm, with parallel recesses of 10-100 nm, all molecules will be parallel and the crystal will become transparent. If an electric voltage is applied to some parts of the liquid crystal, then the liquid crystal state is disturbed. These areas become opaque and begin to glow, while areas without tension remain dark. This phenomenon is used in the creation of liquid crystal TV screens. It should be noted that the screen itself consists of a huge number of elements and the electronic control circuit for such a screen is extremely complex.
Solid state physics Obtaining materials with specified mechanical, magnetic, electrical and other properties is one of the main directions of modern solid state physics. Amorphous bodies occupy an intermediate position between crystalline solids and liquids. Their atoms or molecules are arranged in relative order. Structure understanding solids(crystalline and amorphous) allows you to create materials with desired properties.
"The cycle of sulfur and phosphorus" - From the rocks earth's crust inorganic phosphorus is drawn into the circulation by continental waters. The main sources of inorganic phosphorus are igneous or sedimentary rocks. Sulfur plays an important role in the cycle of substances in the biosphere. Cycle of sulfur in nature. Phosphates deposited at great sea depths do not participate in the small circulation.
"Crystal Grid" - the topic of the lesson CRYSTAL GRID. Classification solids. HCl, Cl2, H2O, NaBr, BaCl2, CaS, O2, NH3, CO2, C. Task: Determine the type chemical bond in these compounds: Characteristics of the main types of crystal lattices.
"Crystalline and amorphous substances" - T pl. Molecular crystal lattice. Developed by the teacher of chemistry MOBU "Lyceum No. 5" of Orenburg Pavlova E.S. Atomic crystal lattice. Aggregate state of matter (on the example of oxygen O2). Examples: simple substances (H2, N2, O2, F2, P4, S8, Ne, He), complex substances (CO2, H2O, sugar C12H22O11, etc.).
"Hazardous Substances" - Types of hazardous substances. Several are determined. int. requirements of PBTs vPvBs some heavy metals. Regulated for discharges throughout the EU. Ethoxylated octylphenols 8a. List of BSAP Priority Substances. Perfluorooctanoic acid 5. Hexabromocyclododecane 6a. Medium chain chlorinated paraffins (chloroalkanes, C14-17) 9. Endosulfan 10.
"Circulation in nature" - The carbon cycle necessarily passes through the biosphere and hydrosphere. Nitrification --- process conversion of ammonia salts to nitric acid salts. Denitrification is the process of reducing ammonia/ammonium, nitrite and nitrate to free nitrogen. Assimilation is a set of synthesis processes in a living organism.
“Amount of Substance” - Map of the study on the topic “Amount of Substance. Shows the mass in 1 mole of a substance. Lesson - research: “Amount of substance. The amount of substance - physical quantity, which. Molar Volume. At n.o. V m \u003d 22.4 l / mol. Designated? (nude). A. Pulls the left cup B. Pulls the right cup C. Scales in balance.
There are 25 presentations in total in the topic
