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__ Vocabulary __ __Alloy-__ a mixture of elements that has metallic properties __Luster-__ metals reflect light or have a shiny appearance __Ductility-__ means the metal can be pulled into wires __Malleability-__ property allows metals and alloys to be hammered or rolled into thin sheets __Conductivity-__ heat or electrical charges can move easily through the material __ Reading Check __ __Pg. 759-__ New copper coin, aluminum foil, horn, wire, flute, shiny necklace, silverware __Pg. 761-__ Automobiles, aircraft bodies, machinery, railroad cars, rails, food cans, knives, roller skates. __Pg. 762-__ Steel is a strong alloy and is used often if a great deal of strength is required __ Caption Questions __ __Pg. 759-__ Malleability is the property allows metals and alloys to be hammered or rolled into thin sheets; ductility means the metal can be pulled into wires __Pg. 761-__ Used to join bones and make task simpler __Pg. 762-__ Alloys help determine the stability of the structure. __ Self Check __ Identify two medical uses of alloys. ~Fixing tooth decay and connecting broken bones. List the properties of metals and alloys. ~Metal: Luster, ductility. Alloy: malleability, conductivity. Both: good conductors of heat Describe how steels are classified. ~Classified by the amount of carbon and other elements present, as well as by the manufacturing process that is used to refine the iron ore. Explain the effects of adding small amounts of another substance to a material. ~By adding small amounts you probably won’t affect the materials appearance by make more at a lower cost. If you were designing a skyscraper in an earthquake zone, what properties would the structural materials need? ~Alloy: malleability and conductivity Calculate the actual amount of gold in 65-g, 14-karat gold necklace. ~58% Gold Calculate number of grams necessary. ~17/2=8.5+7.6= 16.1g __ Vocabulary __ __Ceramics-__ materials that are made from dried clay or claylike mixtures __Semiconductors-__ poor conductors of electricity than metals but better conductors than nonmetals, and their electrical conductivity can be controlled __Doping-__ process of adding impurities or other elements to a semiconductor to modify the conductivity __Integrated circuit-__ contains many semiconducting devices, microchips __ Reading Check __ __Pg. 764-__ Clay, sand, and crystalline rocks. __ Captions Questions __ __Pg. 765-__ Both used in many products that are strong __Pg. 766-__ Hips, knees, shoulders, elbows, fingers, and wrists. __Pg. 768-__ **n-type** is an increase **p-type** is a decrease __Pg. 770-__ Much more highly developed and technical __ Self Check __ Describe how ceramic materials are made. ~Made of clay, sand, and crystalline rocks. List five uses of ceramic materials. ~Glass, pottery, bricks, tile, and concrete. Describe electrical conductivity of ceramics. ~Electrons can move from hole to hole across the crystal, increasing conductivity. Explain what semiconductors are and where they are used. ~Semiconductors perform specific tasks such ass a desktop computer. If you operated a distribution center for a manufacturer, how would you use computers to assist you? ~I may create a database in the computer to help organize what all has been manufactures in the center. What temperature is required to form Ceramic B and what is its density? ~675 degrees Celsius 5.3X4=21.2 g/cm (cubed) How many grams of each component will she need? .35+.65= 1X75= 75g __ Vocabulary __ __Polymer-__ class of natural or manufactured substances that are composed of molecules arranged in large chains with smalls, simple, repeating units called monomers. __Monomer-__ one specific molecules that is repeated in the polymer chain; each link in the chain is called a monomer. __Synthetic-__ the polymer does not occur naturally, but it was manufactured in a laboratory or a chemical plant __Composite-__ mixture of two or more materials-one embedded or layered in the other. __ Reading Check __ __Pg. 774-__ Sealing house windows, house doors, automobile parts, furniture, leather, goods, and trap heat. __Pg. 776-__ Lightweight: cost saving and reducing amount of fuel required to operate the aircraft. __ Self Check __ Explain what a polymer is and give three examples of items that are made from polymers. ~ Class of natural or manufactured substances that are composed of molecules arranged in large chains with smalls, simple, repeating units called monomers; chairs, racket, paint, band aid, tubing, paddles, bags. Identify the raw materials that are used to make most synthetic polymers. ~ Rubber and sulfur Explain what a composite material is and give three examples of items that are made from composites. ~ Mixture of two or more materials-one embedded or layered in the other; construction of satellites, boats, and car bodies. Classify synthetic polymers into groups based upon their uses. ~Hydrocarbons, plastics, fibers, adhesives, surface coating, elastics. How are synthetic polymers creating waste-disposal problems? Discuss possible solutions to this problem. ~If people don’t recycle these objects the decaying process into the environment takes forever to break down. A solution would be to recycle. A telecommunications company launches 10,000-kg satellites. A new satellite made from composites promises to reduce that mass by 25%. What is the mass of the satellite? ~10,000kg/.25= 2,500kg
 * __ Chapter 25- New Materials through Chemistry  __**
 * __ Section 1- Materials with a Past  __**
 * __ Section 2- Versatile Material  __**
 * __ Section 3- Polymers and Composites  __**