UNIT 1 MATERIALS

1. UNIT 1MATERIALS Vocabulary • Names of materials • Characteristics of materials • Adjectives and dimensions • Word formation: SUFFIXES to form ADJECTIVES Grammar and functions • Giving definitions & describing • Articles • Expressing measurements

2. NAMES OF MATERIALS • Aluminium bLight to carry and silvery to look at. • Brass pMixture of copper and zinc. • Bronze oMixture of copper and tin . • Carbon dioxide fGas produced in the combustion of fossil fuels • Chromium lHard, shiny metal used to coat other metals to prevent rust. • Concrete kBuilding material made by mixing cement and gravel. • Copper nSoft, reddish-brown metal, used in wires • Gold gValuable yellow metal which is a very good conductor. • Hydrogen jThe lightest gas and the simplest element in nature • Iron eWith symbol Fe, it is the main component of steel. • Lead rSoft, grey, heavy metal used in pipes, whose symbol is Pb • Mercury dHeavy, silvery metal, usually a liquid at room temperature. • Nitrogen m80% of the air. • Oxygen qColourless and tasteless gas supporting life • Tin iA can is made of it and its symbol is Sn • Uranium cHeavy, white metal whose atoms can be fissioned • Zinc aHard, bluish-white metal used in alloys and in roofing. • Steel hIron plus carbon.

3. VIDEOSECTION 1 : elements found in all stars. Profile of the abundance of elements found in stars: -immense amounts of HYDROGEN and HELIUM. -LOWERamounts (2%) of the heavier elements • Peaks CARBON • OXYGEN • MAGNESIUM • SILICON • SULPHUR • IRON

4. VIDEO Process: nuclear fusion • 2 HYDROGEN atoms= HELIUM + ENERGY-> SUNLIGHT • HELIUM + HELIUM = CARBON • HELIUM + CARBON = OXYGEN • OXYGEN + HELIUM = MAGNESIUM • Right up to IRON • For each of these fusion reactions to occur, INCREASING TEMPERATURE and PRESSURE are needed

5. DESCRIPTIONS • Graphite: a blackish soft allotropic form of (0) carbon, with (0) metallic luster and (0)greasy feel. It consists of layers of carbon atoms. Unlike (0) diamond, (0) graphite is anelectrical conductor . It is used in (0)pencils, (0)coatings and (0)electrodes, as a lubricant, as a moderator in(0)nuclear reactors, and, ina carbon fibre form, as atough light material for (0) sporting equipment • Ceramics: Aceramic material may be defined as aninorganic crystallineoxide material. It is solid and inert. (0)Ceramic materials are brittle, hard, strong in (0) compression, weak in (0) tension. (0) Ceramics can generally withstand (0) very high temperatures • Nylon is a thermoplastic, silky material made ofrepeated units of amide bonds. It is very strong and elastic. It is used to make (0) fabrics, (0) ropes, (0) musical strings, and for(0) mechanical machine components • Petrol isavolatile flammable liquid. It consists of(0) short-chain hydrocarbons. It isused asa fuel especially in(0) internal combustion engines and asa solvent • Plastics:aplastic substance is any of the numerousorganic synthetic or processed materials consisting of(0) very large molecules that are mostly (0) polymers of (0)highmolecular weight and can be made into (0)objects, (0)films, or (0)filaments

6. LISTENING1: what is a metal? • We are so familiar with metals that it might be quite a surprise to be asked the question: What is a metal?. • Take magnesium for example. It burns easily. Why then do we regard magnesium as a metal similar to say iron which willnot burn? • The most important properties that distinguish metals from non-metals are: • they reflect light and thus are shiny • They are good conductors of heat and electricity • They combine with fluorine and chlorine • Most react with acids and with oxygen • Apart from these similarities, metals show a great deal of variation. • Gold, lead and sodium are very soft materials, much softer for example than silicon and graphite, both non-metals. • Many metals corrode easily. • Gold, chromium and platinum, however, do not. • Some metals are very active: sodium, calcium and potassium combine easily with oxygen, chlorine and fluorine. • Gold, silver and mercury, on the other hand, do not form compounds so easily. • Metals far outnumber non-metals: only 20 of the 103 elements known today are non-metallic

7. DESCRIBING • Definition: X is GENERAL CLASS • Composition: It is made (up) of Materials It consists of Substances It has Components It is composed of Parts It is formed by Pieces • Characteristics: To be + ADJ Shape (circular, elliptical) To look + ADJ Properties (flexible, tough) To seem +ADJ Colour (blue, greenish) To become + ADJ Texture (hard, smooth) Temperature (warm, cold) Dimensions (long, thin, small) To have + NOUN • Applications: X is used for (+GER) / to (+INF) X is used in/as (+NOUN) X serves to (+INF)

8. ARTICLES • .... Ø...corrosion is ...a...very serious problem in Ø. metallic structures. • .. Ø..iron is used in ... Ø. engineering due to ...its..... strength. • ....the.. physical properties of .... Ø. matter will be studied in Ø chapter 3. • Ø fission is one of ....the.. two types of Ø nuclear reactions which release Ø large amounts of Ø energy. The fission of Ø Uranium atoms is used in Ø nuclear power plants to generate Ø electricity. • The major component of Ø steel is Ø iron, a metal that in its pure state is not much harder than Ø copper. • Ø silicon is used as a semiconductor in the manufacture of Ø chips. • Ø plastics may be classified into two major groups according to their chemical composition. • Ø mathematics is basic for an engineer. • An alloy is a metallic substance composed of two or more elements as either a compound or a solution. • In Ø Kevlar, an artificial fiber, the molecules lie straight, giving it Ø/its strength and Ø/its stiffness

9. ARTICLES: MERCURY Ømercury is a/the chemical element whose symbol is Hg. It is a silvery-white, heavy, liquid metal. Compared with other metals, it is a poor conductor of Ø heat and a fair conductor of Ø electricity. Ø mercury is the only common metal that is a liquid at Ø ordinary temperatures. It easily forms Ø alloys with many other metals. When it combines with certain metals (such as Ø silver, Ø zinc or Ø tin), the resulting alloy is called an amalgam. Both the element and Ø most of its compounds are poisonous. Ø mercury and its compounds are used in Ø electrolytic cells, Ø dentistry, Ø thermometers, Ø batteries, and in Ø medicine.

10. VOCABULARY: Adjectives TEMPERATURE: Boiling, Molten, Cool, warm, Burning, Icy TEXTURE: rough, hard, smooth, soft, sticky SHAPE: rectangular, straight, cylindrical, square, rounded, sharp, curved COMPOSITION: metallic, plastic, ferrous, synthetic, organic, golden SIZE: huge, tiny, minute, large, broad, short COLOUR: light, bright, dark, opaque, reddish, golden

11. WORD FORMATION: Adjectives ADJECTIVES FROM NOUNS LATIN ORIGIN OR ROOT ENGLISH ORIGIN -IC atomic -FUL beautiful -AL/AR usual/linear -LESS harmless -OUS poisonous/ lustrous -(L)Y sunny -ISH yellowish ADJECTIVES FROM VERBS -ING boring -ED concentrated ADJECTIVES FROM VERBS OR NOUNS (usually from a Latin origin) -IBLE/ -ABLE responsible/drinkable -ENT / -ANT different/important -IVE destructive

12. WORD FORMATION STAINLESS STEELS • StainLESS steels contain chromium, nickel • and other alloyING elements • that keep them rust resistANT • in spite of the action of moisture or corrosIVE acids and gases. • Some steels have unusUAL strength. • Because of their shinY surfaces • architects wideLY use them • for decoratIVE purposes.

13. LISTENING: Temperatures • The most commonly used metal in industry is IRON. Its symbol is Fe, its atomic weight 55.19and its specific weight is 7.86 GR/CM3. Its melting point is 1,528ºC; this is a metal which is magnetized quite strongly but above 768ºC it cannot be magnetized. • Another metal of a great importance in engineering is ALUMINIUM, with an atomic weight of 26.97, a specific weight of 2.7 GR/CM3 and its melting point is 658ºC • Among metals, LEAD is the metal which possesses the highest density, with an atomic weight of 207.22 and a specific weight of 11.34 GR/CM3; contrarily to other metals, however, its melting point is relatively low as it melts at 327ºC.

14. LISTENING: Temperatures • However not all metals have the same characteristics; as an example we have MERCURY which is A LIQUID at room temperature; thus, the temperature at which this metal changes from liquid to solid is –38.9ºC and its boiling point is 357.2ºC. • Non-metals, on the other hand, vary greatly with regard to their characteristics. For example, CHLORINE has a specific weight of 0.0032 GR/CM3 and its boiling point is –33.7ºC. However, SILICON, whose specific weight is 2.33, melts at 1,310ºC and boils at 2,355ºC.

15. MEASUREMENTS • X is 3 m +ADJ (eg: The bar is 3m LONG) • X is 3m + IN + NOUN (eg:the bar is 3m IN LENGTH) • X has a +NOUN + OF 3m (eg: the bar has A LENGTH OF 3m) • The NOUN + OF X is 3m (eg: THE LENGTH OF the bar is 3m) What is it like? HOW + ADJ /WHAT + NOUN Is this object? (eg: HOW LONG / WHAT SHAPE is the component? It is3m long / rectangular

16. EXERCISE: Measurements • The film coating the piece must be very THIN. It should be 0.05 mm THICK • The light travels along THE LENGTH of the optical fibre • How HIGH is the new tower? It is 10ft HIGH • To make chips, a single crystal in the shape of a long bar of about 10 cm IN diameter is cut into circular slices 1/2 mm THICK • The beams needed for the structure must be 3 m LONG and 25 cm THICK/WIDE • To take the recordings, the thermometer was placed at a HEIGHT of 1.5 m above ground level. • The piece of the machine is too long to fit in the slot, so we must make it SHORTER • 3-D objects have three main dimensions: HEIGHT, WIDTH and LENGTH • The reaction produces a layer on top of the solution, with THICKNESSES ranging from 0.2 to 0.6 mm • WHAT IS THE PIECE LIKE? /WHAT SHAPE is it?. Well, it is cylindrical

17. LISTENING: Dimensions CHARACTERISTICS OF THE ALLOY: • Stands very high and very low temperatures • melting point= 3,527ºC,below -58ºC DIMENSIONS: • 2.35m high, • width =37 cm • 1.55m length of its base – 1.05cm top • it weights 782 kg PERFORMANCE: • 1700 hours • 350 rpu (revolutions per unit)