Analía Bellizzi – Chemistry Classes

Ronald Reagan Senior High School


From your syllabus
9.1 Properties of metals

1 Compare the general physical properties of metals and non-metals, including:
(a) thermal conductivity
(b) electrical conductivity
(c) malleability and ductility
(d) melting points and boiling points
2 Describe the general chemical properties of metals, limited to their reactions with:
(a) dilute acids
(b) cold water and steam
(c) oxygen

9.2 Uses of metals

1 Describe the uses of metals in terms of their physical properties, including:
(a) aluminium in the manufacture of aircraft because of its low density
(b) aluminium in the manufacture of overhead electrical cables because of its low density and good electrical conductivity
(c) aluminium in food containers because of its resistance to corrosion
(d) copper in electrical wiring because of its good electrical conductivity and ductility

9.3 Alloys and their properties

1 Describe an alloy as a mixture of a metal with other elements, including:
(a) brass as a mixture of copper and zinc
(b) stainless steel as a mixture of iron and other elements such as chromium, nickel and carbon
2 State that alloys can be harder and stronger than the pure metals and are more useful
3 Describe the uses of alloys in terms of their physical properties, including stainless steel in cutlery because of its hardness and resistance to rusting
4 Identify representations of alloys from diagrams of structure
5 Explain in terms of structure how alloys can be harder and stronger than the pure metals because the different sized atoms in alloys mean the layers can no longer slide over each other

9.4 Reactivity series

1 State the order of the reactivity series as:
potassium, sodium, calcium, magnesium, aluminium, carbon, zinc, iron, hydrogen, copper,
silver, gold
2 Describe the reactions, if any, of:
(a) potassium, sodium and calcium with cold water
(b) magnesium with steam
(c) magnesium, zinc, iron, copper, silver and gold with dilute hydrochloric acid and explain these reactions in terms of the position of the metals in the reactivity series
3 Deduce an order of reactivity from a given set of experimental results
4 Describe the relative reactivities of metals in terms of their tendency to form positive ions, by displacement reactions, if any, with the aqueous ions of magnesium, zinc, iron, copper and silver
5 Explain the apparent unreactivity of aluminium in terms of its oxide layer

9.5 Corrosion of metals

1 State the conditions required for the rusting of iron and steel to form hydrated iron(III) oxide
2 State some common barrier methods, including painting, greasing and coating with plastic
3 Describe how barrier methods prevent rusting by excluding oxygen or water
4 Describe the use of zinc in galvanising as an example of a barrier method and sacrificial protection
5 Explain sacrificial protection in terms of the reactivity series and in terms of electron loss

9.6 Extraction of metals

1 Describe the ease in obtaining metals from their ores, related to the position of the metal in the reactivity series
2 Describe the extraction of iron from hematite in the blast furnace, limited to:
(a) the burning of carbon (coke) to provide heat and produce carbon dioxide
(b) the reduction of carbon dioxide to carbon monoxide
(c) the reduction of iron(III) oxide by carbon monoxide
(d) the thermal decomposition of calcium carbonate /limestone to produce calcium oxide
(e) the formation of slag
3 State that the main ore of aluminium is bauxite and that aluminium is extracted by electrolysis Supplement
4 State the symbol equations for the extraction of iron from hematite
(a) C + O2 → CO2
(b) C + CO2 → 2CO
(c) Fe2O3 + 3CO → 2Fe + 3CO2
(d) CaCO3 → CaO + CO2
(e) CaO + SiO2 → CaSiO3
5 Describe the extraction of aluminium from purified bauxite / aluminium oxide, including:
(a) the role of cryolite
(b) why the carbon anodes need to be regularly replaced
(c) the reactions at the electrodes, including ionic half-equations
Details of the purification of bauxite are not required