1. L_ _ _ is a very heavy, soft, dark grey poisonous metal, usually in the center of pencils. 2. The machines should be made of ­­­d_ _ _ _ _ _ materials so that they can be used for a long time. 3. Iron is a r_ _ _ _ metal that is used to make steel so it's hard to bend. 4. Copper is used for wire because it is more d_ _ _ _ _ _ than most other metals. 5. The pipe needs to bend several times as we pass it into the structure, so we don’t want it to be stiff. We should choose a f_ _ _ _ _ _ _ pipe. 6. Glass which is a b_ _ _ _ _ _ material used in the production of our mobile phones may break if the phone is dropped. 7. High temperature super alloys are used in applications requiring material that can w_ _ _ _ _ _ _ _ extreme forces and severe oxidizing. 8. T_ _ _ _ _ _ _ is a chemical element that is a light, strong, white metal. Its symbol is Ti. 9. Copper can be mixed with tin and led to produce b_ _ _ _ _. 10. T_ _ _ _ _ _ _ _ _ _ _ _ _ can be melted and formed into shapes that become hard, and can then be melted again.

Assertion (A): The connecting wires are made of copper.Reason (R): The electrical conductivity of copper is high.

What are the materials used for brushes in dc machines?a.Steelb.Aluminiumc.Irond.Carbon

QUESTION THREEa. List the four classifications of steels and briefly describe the properties of each.(10 marks)b. What property of titanium makes it attractive for use in race-car and jet-enginecomponents? (2 marks)c. Why is magnesium often used as a structural material in power hand tools? Why are itsalloys used instead of pure magnesium? (3 marks)d. List two examples of refractory materials. Which property of the refractory metalsdefines their most useful applications? (2 marks)e. What are shape-memory alloys (SMAs)? (3 marks)SECTION CQUESTION FOURa. Cite the four factors that influence corrosion. (2 marks)b. Briefly describe the following forms of corrosion, and for each, cite measures that can betaken to prevent or control it. (8 marks)i. Galvanic corrosionii. Crevice corrosioniii. Intergranular corrosioniv. Erosion–Corrosionc. A piece of corroded metal alloy plate was found in a submerged ocean vessel. It wasestimated that the original area of the plate was 800 cm2 and that approximately 7.6 kg hadcorroded away during the submersion. Assuming a corrosion penetration rate of 4 mm/yr forthis alloy in seawater, estimate the time of submersion in years. The density of the alloy is4.5 g/cm3. (3 marks)a. Compare the effectiveness of quenching in moderately agitated water and oil by graphing ona single plot radial hardness profiles for cylindrical specimens of an 8630 steel of diameter65 mm that have been quenched in both media. Use Figure 2 and Figure 3. (7 marks)

Describe features of these pieces of lab equipment that the others lack? Try to come up with 3–4 features.For example, the Bunsen burner and tripod are both made of metal.

3. An element that is generally shiny, easily pulled into wires, hammered into thin sheets, good conductor. ___________4. Ability of a metal to reflect light. _________________________5. The ability of a substance to be hammered or rolled into thin sheets. ___________________6. Elements that have no metallic properties. _____________________7. An element that has physical and chemical properties of both metals and nonmetals. _____________________8. Conducts electricity at high temperatures, but not at low temperatures. ________________________9. The ability to be pulled into thin wires. ___________________________10. The elements in group 18. _______________________________11. What information about an element is usually included on an element key?12. Mendeleev arranged the table by atomic _____________ and Mosely arranged the table by atomic ____________.