Metals & Materials Quiz

1. What is the reactivity series of metals?

1. A list of metals in alphabetical order
2. A list of metals ranked by their density
3. A list of metals ranked by their electrical conductivity
4. A list of metals ranked by their reactivity with water, acids, and oxygen — from most to least reactive

2. Which metal is the most reactive?

1. Aluminium
2. Gold
3. Iron
4. Potassium

3. What is an alloy?

1. A metal extracted directly from ore
2. A metal oxide formed by corrosion
3. A mixture of two or more elements, at least one of which is a metal
4. A pure metal with high conductivity

4. Why are alloys generally harder than pure metals?

1. Because alloys are less dense than pure metals
2. Because alloys have lower melting points
3. Because alloys have more electrons
4. Because different-sized atoms disrupt the regular lattice, making it harder for layers to slide over each other

5. What is corrosion?

1. The extraction of metals from their ores
2. The gradual deterioration of a metal by chemical reaction with its environment (especially with oxygen and water)
3. The polishing of metal surfaces
4. The process of melting metals at high temperature

6. What conditions are needed for iron to rust?

1. Both water and oxygen
2. Carbon dioxide and water
3. Oxygen only
4. Water only

7. What is galvanising?

1. Coating iron or steel with a layer of zinc to protect against corrosion
2. Coating iron or steel with copper to prevent corrosion
3. Passing electricity through a metal to harden it
4. Treating metal with acid

8. Why does aluminium not appear to corrode despite being a reactive metal?

1. Aluminium forms a thin, protective oxide layer that prevents further reaction with oxygen
2. Aluminium is actually unreactive
3. Aluminium is stored in a special coating from manufacture
4. Aluminium only reacts at very high temperatures

9. What are the typical physical properties of metals?

1. Brittle, dull, poor conductors, low melting point
2. Hard, brittle, good conductors of electricity only
3. Shiny, malleable, ductile, good conductors of heat and electricity, high melting point
4. Soft, transparent, non-conductive, low density

10. What is stainless steel and what makes it corrosion-resistant?

1. An alloy of iron with at least 10.5% chromium; the chromium forms a protective oxide layer
2. Pure iron with carbon removed; it does not rust
3. Steel coated with nickel; nickel is unreactive
4. Steel coated with zinc; zinc prevents oxidation

11. What is smelting?

1. Extracting metals from their ores by heating with a reducing agent (such as carbon) at high temperatures
2. Testing the purity of a metal
3. The process of forming alloys
4. The process of polishing metals to a high shine

12. What is a semiconductor?

1. A half-metal found between metals and non-metals on the periodic table
2. A material that only conducts electricity under pressure
3. A material with electrical conductivity between that of a conductor and an insulator, which can be controlled
4. A metal that conducts electricity only at low temperatures

13. What are shape memory alloys?

1. Alloys that become stronger when cooled
2. Alloys that change colour when deformed
3. Alloys that remember their chemical composition
4. Alloys that return to a pre-programmed shape when heated after being deformed

14. What is electrolysis used for in metallurgy?

1. Extracting highly reactive metals (like aluminium and sodium) that cannot be reduced by carbon
2. Galvanising steel
3. Smelting iron from iron ore
4. Testing the purity of gold

15. What are ceramics and what are their key properties?

1. Magnetic materials used in electronics
2. Metal alloys used in construction
3. Non-metallic inorganic solids that are hard, brittle, heat-resistant, and electrical insulators
4. Synthetic polymers used in clothing

16. What is the displacement reaction between zinc and copper sulfate solution?

1. Both metals dissolve in solution
2. Copper displaces zinc: Cu + ZnSO₄ → CuSO₄ + Zn
3. No reaction occurs because zinc is less reactive than copper
4. Zinc displaces copper: Zn + CuSO₄ → ZnSO₄ + Cu, because zinc is more reactive than copper

17. What is a composite material?

1. A material made of a single element with specific properties
2. A material made of two or more components with different properties, combining the best of each
3. A type of ceramic with metallic properties
4. Any material that contains carbon

18. Gold is described as a 'noble metal'. What does this mean?

1. It has the highest melting point of all metals
2. It is highly resistant to corrosion and oxidation, and does not react with most acids
3. It is only found in royal jewellery
4. It is the most expensive metal

19. What property makes metals good electrical conductors?

1. The presence of delocalised (free) electrons that can move through the metallic lattice
2. Their crystalline structure
3. Their high density
4. Their high melting points

20. What is titanium valued for in aerospace and medical applications?

1. Its ability to conduct electricity better than copper
2. Its combination of low density, very high strength, excellent corrosion resistance, and biocompatibility
3. Its extremely low cost compared to steel
4. Its higher melting point than all other metals